vciy

CVE-2017-9788

INDEX BUILT · 2026-09-20

No source can show you its own past. This one can.

Print this page to keep the view as it stands on this date. Everything hidden behind a disclosure opens, and every receipt prints with its value.

In Apache httpd before 2.2.34 and 2.4.x before 2.4.27, the value placeholder in [Proxy-]Authorization headers of type 'Digest' was not initialized or…

CVE-2017-97884 of 4 sources documented this
51

rank 51 = 14 + 23 + 4 + 10 + 0

rank@v1 · this cycle

Someone is already using it

CISA KEV catalog · public proof-of-concept · FIRST EPSS

EPSS 0.56770  ·  without this subject the record ranks 37

What it costs you if it fires

NVD CVSS base score, then the CNA's own

CVSS 9.1, from NVD  ·  without this subject the record ranks 28

It is getting worse, not staying still

FIRST EPSS series, rescorings and bad loads removed

rose on 2026-01-04  ·  without this subject the record ranks 47

How much of the world it touches

NVD CPE configurations

20 products in the CPE ranges  ·  without this subject the record ranks 41

Someone else already set the date

CISA KEV remediation due date

no CISA due date  ·  without this subject the record ranks 51

Unaudited dollar value2 of 3 inputs carry a receipt
Exposure$2.50Mover the next 30 days, if this record is yours
Movement-$140,000on 2026-04-27, the last material move, 4 months before this reading
Basisassumeda published average, not your estate

$2.50M = $4.99M incident cost x 0.8814887365328109 exposure x 0.5677 likelihood

udv@v1 · unaudited · wrong for you until you say what you run

$4.99M is the cost of a breach that happened, from IBM Cost of a Data Breach Report 2026, global average. It is not the value of any asset of yours. That average already covers breaches of every severity, so scaling it by exposure understates a partial-impact record. That is an assumption, not a measurement. Your own asset value goes in the decision record.

Hindsight · the state

0.5677EPSSNOT IN KEVas of 2026-09-20
Severity9.1 CRITICALreceipt
Harmunauthenticated · networkreceipt
Exploitationnone in held sources
Defenseunaffected versions publishedreceipt
Movementdoubled within 72hreceipt
PLATEAU10Minimal movement since 2026-03-04, 186 days at 0.57, as of 2026-09-06. arc-rules@v1

Foresight · where to check next

CVE-2022-47966CVE-2022-29499VMware vCenterApache Log4j2QNAP Systems Inc.Microsoft9788

This record is one instance of CWE-20, improper input validation. The index holds 13347 prior instances of this class, 73 KEV-listed. The nearest of its KEV-listed records are drawn beside this. taxonomy@v1

Full pattern panel

Prior records in this weakness class. Each is its own record, dated and receipted.
Color is a claim, not decoration:the hostile worldthe defenseno signalspoke length is how much of the record matches, not how bad it is

Running Apache HTTP Server? Check your version

A deterministic range check against the ranges this record publishes. It tells you where a version sits in the record, not whether your deployment is exploitable. No account needed.

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Harm, if it fires from the vector and the weakness

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Reachnetwork-reachable · no privileges required · no user interaction · low attack complexityreceipt
ImpactComplete confidentiality and availability lossreceipt
Scored fromCVSS v3.0 · NVD's vectorreceipt
Weakness classCWE-20 Improper Input Validation; CWE-200 Exposure of Sensitive Information to an Unauthorized Actorreceipt
Published consequencesCWE-20: Availability: DoS: Crash, Exit, or Restart, DoS: Resource Consumption (CPU), DoS: Resource Consumption (Memory); Confidentiality: Read Memory, Read Files or Directories…[email protected]

CISA KEV & Federal Remediation Deadline from the record and CISA

The fix, and how long it's been waiting.

First unaffected version, by branchmac os x 10.13.1receipt
Patch available sinceNo dated patch-availability record in held sources. The index holds reference URLs without dates and only the current revision of the CVE record, so the day a fix first existed cannot be derived. Only the versions it landed in.

Exploit Status & Known PoCs a ladder, not a score

Current rung: Nothing observed in held sources.

  • RUNG 1Nothing observed in held sources
  • RUNG 2Proof-of-concept published
  • RUNG 3Exploited in the wild · CISA KEV listed
  • RUNG 4Ransomware campaign use known

Authority who says so

CVSS, NVD9.1 CRITICALreceipt
Exploit probability0.5677 · top 0.98% of all CVEsreceipt
Blast breadth8 products across 4 vendorsderived
Assigned byapachereceipt
Recorded changes73 · last 19 Sep 2026derived

Affected & Fixed Versions as published

Affected productApache Software Foundation Apache HTTP Serverreceipt
Published rangesapache http server <= 2.2.33; apache http server >= 2.4.0 <= 2.4.26; redhat enterprise linux server 6.0; redhat enterprise linux server 7.0receipt
Show all 20 published ranges
apache http server <= 2.2.33
apache http server >= 2.4.0 <= 2.4.26
redhat enterprise linux server 6.0
redhat enterprise linux server 7.0
redhat enterprise linux server aus 7.2
redhat enterprise linux server aus 7.3
redhat enterprise linux server aus 7.4
redhat enterprise linux server aus 7.6
redhat enterprise linux server eus 6.7
redhat enterprise linux server eus 7.2
redhat enterprise linux server eus 7.3
redhat enterprise linux server eus 7.4
redhat enterprise linux server eus 7.5
redhat enterprise linux server eus 7.6
redhat enterprise linux server tus 7.2
debian linux 8.0
debian linux 9.0
apple mac os x < 10.13.1
redhat enterprise linux desktop 6.0
redhat enterprise linux desktop 7.0

A rung lights from a row in the index, never from an assessment. "Held sources" is the true scope of the claim: this index reads the CVE record, NVD, CISA KEV, FIRST's EPSS and public proof-of-concept repositories, and it does not observe attacks.

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What it is stated by the CNA

In Apache httpd before 2.2.34 and 2.4.x before 2.4.27, the value placeholder in [Proxy-]Authorization headers of type 'Digest' was not initialized or reset before or between successive key=value assignments by mod_auth_digest. Providing an initial key with no '=' assignment could reflect the stale value of uninitialized pool memory used by the prior request, leading to leakage of potentially confidential information, and a segfault in other cases resulting in denial of service. receipt

NVD's analysis a second authority

severity
9.1 CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
weakness
CWE-20; CWE-200
affected versions
apache http server <= 2.2.33; apache http server >= 2.4.0 <= 2.4.26; redhat enterprise linux server 6.0; and 17 more, listed in full below

check it yourself access.redhat.com support.apple.com access.redhat.com access.redhat.com support.hpe.com httpd.apache.org +14 morereceipt

Dated events

2023-03-07EPSS moved 0.08 to 0.902026-06-15EPSS moved 0.49 to 0.57

Movement the material steps

14 Apr 20210.04793
7 Mar 20230.89922 · crossed 0.10 and 0.50 · scoring model v2023.03.01
28 Apr 20230.90456 · crossed 0.90
8 May 20230.89317 · crossed 0.90
8 Nov 20230.53945
8 Feb 20240.46783 · crossed 0.50
28 Feb 20250.50058 · crossed 0.50
17 Mar 20250.52365 · scoring model v2025.03.14
29 Mar 20250.75855
30 Mar 20250.55534
1 May 20250.25668 · crossed 0.50
4 May 20250.54971 · crossed 0.50
1 Jun 20250.25788 · crossed 0.50
4 Jun 20250.5439 · crossed 0.50
1 Jul 20250.27547 · crossed 0.50
4 Jul 20250.57147 · crossed 0.50
1 Aug 20250.23364 · crossed 0.50
4 Aug 20250.55918 · crossed 0.50
1 Sep 20250.19833 · crossed 0.50
4 Sep 20250.51082 · crossed 0.50
11 Sep 20250.46046 · crossed 0.50
1 Oct 20250.25301
4 Oct 20250.47951
9 Oct 20250.50378 · crossed 0.50
27 Oct 20250.48487 · crossed 0.50
28 Oct 20250.50378 · crossed 0.50
1 Nov 20250.27348 · crossed 0.50
4 Nov 20250.52641 · crossed 0.50
18 Nov 20250.76898
21 Nov 20250.52641
1 Dec 20250.27564 · crossed 0.50
4 Dec 20250.52641 · crossed 0.50
27 Dec 20250.48939 · crossed 0.50
28 Dec 20250.50826 · crossed 0.50
1 Jan 20260.25997 · crossed 0.50
4 Jan 20260.52641 · crossed 0.50
1 Feb 20260.28075 · crossed 0.50
4 Feb 20260.53216 · crossed 0.50
1 Mar 20260.27564 · crossed 0.50
4 Mar 20260.52641 · crossed 0.50
27 Apr 20260.47063 · crossed 0.50
15 Jun 20260.5677 · crossed 0.50 · scoring model v2026.06.15
6 Sep 20260.5677

This score more than doubled inside 72 hours. Both observations are in the full history below.

Show all 73 observations
14 Apr 20210.04793
27 Apr 20210.049
3 Jun 20210.05006
8 Jun 20210.05325
4 Feb 20220.07767
7 Mar 20230.89922
28 Apr 20230.90456
8 May 20230.89317
8 Sep 20230.88876
17 Oct 20230.87239
8 Nov 20230.53945
8 Feb 20240.46783
17 Dec 20240.46149
28 Feb 20250.50058
17 Mar 20250.52365
18 Mar 20250.5439
22 Mar 20250.54956
29 Mar 20250.75855
30 Mar 20250.55534
4 Apr 20250.54971
1 May 20250.25668
4 May 20250.54971
21 May 20250.55534
30 May 20250.54956
1 Jun 20250.25788
3 Jun 20250.25301
4 Jun 20250.5439
19 Jun 20250.57147
1 Jul 20250.27547
4 Jul 20250.57147
27 Jul 20250.57701
30 Jul 20250.55918
1 Aug 20250.23364
4 Aug 20250.55918
10 Aug 20250.51082
16 Aug 20250.51662
29 Aug 20250.51082
1 Sep 20250.19833
4 Sep 20250.51082
11 Sep 20250.46046
1 Oct 20250.25301
4 Oct 20250.47951
9 Oct 20250.50378
27 Oct 20250.48487
28 Oct 20250.50378
1 Nov 20250.27348
2 Nov 20250.27564
4 Nov 20250.52641
18 Nov 20250.76898
21 Nov 20250.52641
1 Dec 20250.27564
4 Dec 20250.52641
14 Dec 20250.50243
18 Dec 20250.50826
27 Dec 20250.48939
28 Dec 20250.50826
1 Jan 20260.25997
2 Jan 20260.25508
4 Jan 20260.52641
25 Jan 20260.53216
1 Feb 20260.28075
4 Feb 20260.53216
7 Feb 20260.52641
1 Mar 20260.27564
4 Mar 20260.52641
22 Apr 20260.50243
27 Apr 20260.47063
10 May 20260.49498
15 Jun 20260.5677
23 Aug 20260.53687
30 Aug 20260.5677
5 Sep 20260.53687
6 Sep 20260.5677

73 observations held. A highlighted step crossed a promotion threshold. A step marked with a scoring model moved because the instrument was replaced, not because the vulnerability changed. receipt

The full biography

EPSS 0.5677Published2017-07-13Index as of2026-09-06

Exploit probability more than doubled between 2025-05-01 and 2025-05-04 (0.25668 → 0.54971) and the record had been public for 9 years, 1 month when this index was last written.

Published 2017-07-13 receipt · Index as of 2026-09-06 derived

The pattern, elsewhere

This record is one instance of CWE-20, improper input validation. The index holds 13347 prior instances of this class, 73 KEV-listed. The nearest of its KEV-listed records are drawn beside this. [email protected]

CVE-2022-47966matches 7 of 9KEV listed · 2023receipt
CVE-2022-29499matches 7 of 9KEV listed · 2022receipt
CVE-2021-21985 · VMware vCenter Server and VMware Cloud…matches 7 of 10KEV listed · 2021receipt
CVE-2021-44228 · Apache Log4j2matches 7 of 10KEV listed · 2021receipt
CVE-2018-19949 · QNAP Systems Inc. QTSmatches 7 of 10KEV listed · 2020receipt
CVE-2019-0604 · Microsoft SharePoint Servermatches 7 of 10KEV listed · 2019receipt

"Matches n of m" counts the attributes the two records can both be compared on: the CVSS metrics they share a version of, any weakness class beyond this one, and the vendor. fit-rules@v1

13347 records in this class held. The six above are drawn from the ones CISA has listed as exploited, ranked by how much of the record matches this one. That is why every one of them is KEV-listed: the pool is, so the colour on those spokes says nothing the pool has not already said.

No curated product neighbourhood is held for this product, so the records above are the nearest this index can name. The neighbourhood table covers a small set of products and is extended by hand.

Siblings and hubs

Records related to this one

Its defect family

apache software foundation apache http server

Of the 3 records in this family that state one, this holds the highest NVD CVSS score: 9.1.

Grouped by shared product and weakness, not by shared vulnerability. Each record's own state is on its own page.

Family membership: held values

This record is one of a group, and the group's page describes all of them. This page is kept and dated, and the defect family's own page is the one we offer for indexing: the whole group.

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What usually comes next

Everything above needs no account. What is below is work: assembling it, scoping it to your estate, watching it, and handing it to someone else.

Everything on this page is free. Public data. Withholding it protects nothing.