vciy

CVE-2020-26116

INDEX BUILT · 2026-09-20

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http.client in Python 3.x before 3.5.10, 3.6.x before 3.6.12, 3.7.x before 3.7.9, and 3.8.x before 3.8.5 allows CRLF injection if the attacker…

CVE-2020-261163 of 4 sources documented this
29

rank 29 = 2 + 18 + 0 + 9 + 0

rank@v1 · scheduled

Someone is already using it

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

EPSS 0.06358  ·  without this subject the record ranks 27

What it costs you if it fires

NVD CVSS base score, then the CNA's own

CVSS 7.2, from NVD  ·  without this subject the record ranks 11

It is getting worse, not staying still

FIRST EPSS series, rescorings and bad loads removed

no persisting rise in 365 days  ·  without this subject the record ranks 29

How much of the world it touches

NVD CPE configurations

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

Someone else already set the date

CISA KEV remediation due date

no CISA due date  ·  without this subject the record ranks 29

Unaudited dollar value2 of 3 inputs carry a receipt
Exposure$136,000over the next 30 days, if this record is yours
Movement-$443,000on 2022-04-01, the last material move, 4 years, 4 months before this reading
Basisassumeda published average, not your estate

$136,000 = $4.99M incident cost x 0.42806422275080447 exposure x 0.06358 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

0.06358EPSSNOT IN KEVas of 2026-09-20
Severity7.2 HIGHreceipt
Harmunauthenticated · networkreceipt
Exploitationnone in held sources
Defenseunaffected versions publishedreceipt
Movementdoubled within 72hreceipt
PLATEAU10Minimal movement since 2022-04-01, 1610 days at 0.06, as of 2026-08-28. arc-rules@v1

Foresight · where to check next

AtlassianCVE-2022-27924Cisco IdentityCorporation TapeCVE-2022-3591426116

This record is one instance of CWE-74, improper neutralization of special elements in output used by a downstream component ('injection'). The index holds 5545 prior instances of this class, 13 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

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Reachnetwork-reachable · no privileges required · no user interaction · low attack complexityreceipt
ImpactPartial confidentiality and integrity loss, with impact beyond the vulnerable componentreceipt
Scored fromCVSS v3.1 · NVD's vectorreceipt
Weakness classCWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')receipt
Published consequencesCWE-74: Confidentiality: Read Application Data; Access Control: Bypass Protection Mechanism; Other: Alter Execution Logic; Integrity, Other: Other; Non-Repudiation: Hide Activities[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 branchpython 3.5.10; python 3.6.12; python 3.7.9; python 3.8.5receipt
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, NVD7.2 HIGHreceipt
Exploit probability0.06358 · top 7% of all CVEsreceipt
Blast breadth6 products across 6 vendorsderived
Assigned bymitrereceipt
Recorded changes78 · last 19 Sep 2026derived

Affected & Fixed Versions as published

Named in the CPE rangesPython; Canonical ubuntu linux; Fedoraproject fedora; and 3 morereceipt
Published rangespython >= 3.0.0 < 3.5.10; python >= 3.6.0 < 3.6.12; python >= 3.7.0 < 3.7.9; python >= 3.8.0 < 3.8.5receipt
Show all 14 published ranges
python >= 3.0.0 < 3.5.10
python >= 3.6.0 < 3.6.12
python >= 3.7.0 < 3.7.9
python >= 3.8.0 < 3.8.5
fedoraproject fedora 31
fedoraproject fedora 32
fedoraproject fedora 33
canonical ubuntu linux 12.04
canonical ubuntu linux 14.04
canonical ubuntu linux 16.04
canonical ubuntu linux 18.04
debian linux 9.0
oracle zfs storage appliance kit 8.8
opensuse leap 15.1

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

http.client in Python 3.x before 3.5.10, 3.6.x before 3.6.12, 3.7.x before 3.7.9, and 3.8.x before 3.8.5 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of HTTPConnection.request. receipt

NVD's analysis a second authority

severity
7.2 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
weakness
CWE-74
affected versions
python >= 3.0.0 < 3.5.10; python >= 3.6.0 < 3.6.12; python >= 3.7.0 < 3.7.9; and 11 more, listed in full below

check it yourself python-security.readthedocs.io bugs.python.org lists.fedoraproject.org lists.fedoraproject.org lists.fedoraproject.org usn.ubuntu.com +8 morereceipt

Dated events

2021-06-19EPSS moved 0.03 to 0.112022-04-01EPSS moved 0.23 to 0.032026-06-15EPSS moved 0.01 to 0.06

Movement the material steps

14 Apr 20210.02678
19 Jun 20210.1099 · crossed 0.10
24 Jun 20210.02678 · crossed 0.10
6 Jan 20220.11741 · crossed 0.10
4 Feb 20220.23437
1 Apr 20220.02686 · crossed 0.10
7 Mar 20230.00176 · scoring model v2023.03.01
17 Mar 20250.0034 · scoring model v2025.03.14
15 Jun 20260.06283 · scoring model v2026.06.15
28 Aug 20260.06358

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

Show all 78 observations
14 Apr 20210.02678
19 Jun 20210.1099
24 Jun 20210.02678
21 Oct 20210.0288
6 Jan 20220.11741
4 Feb 20220.23437
1 Apr 20220.02686
7 Mar 20230.00176
3 May 20230.00214
25 May 20230.00247
8 Jul 20230.00198
5 Aug 20230.00281
8 Nov 20230.00263
29 Dec 20230.00216
30 Jan 20240.00306
3 Sep 20240.00350
17 Dec 20240.00199
21 Jan 20250.00139
17 Mar 20250.0034
22 Mar 20250.006
23 Mar 20250.0034
27 Mar 20250.0055
28 Mar 20250.00312
29 Mar 20250.00524
30 Mar 20250.00312
31 Mar 20250.0055
1 Apr 20250.00312
8 Apr 20250.0055
9 Apr 20250.00312
17 Apr 20250.0055
18 Apr 20250.00312
19 Apr 20250.0055
20 Apr 20250.00312
1 May 20250.0055
4 May 20250.00312
1 Jun 20250.0055
6 Jun 20250.00312
15 Jun 20250.00513
19 Jun 20250.00471
21 Jun 20250.00928
24 Jun 20250.00471
1 Jul 20250.00928
4 Jul 20250.00471
30 Jul 20250.00579
1 Aug 20250.0125
6 Aug 20250.00579
1 Sep 20250.0125
5 Sep 20250.00579
1 Oct 20250.01023
4 Oct 20250.00577
25 Oct 20250.00531
27 Oct 20250.00534
28 Oct 20250.00531
1 Nov 20250.00943
4 Nov 20250.00531
18 Nov 20250.01546
21 Nov 20250.00531
1 Dec 20250.00943
4 Dec 20250.00531
18 Dec 20250.00906
24 Dec 20250.00832
27 Dec 20250.00836
28 Dec 20250.00832
1 Jan 20260.0128
4 Jan 20260.00832
22 Jan 20260.00906
27 Jan 20260.00983
1 Feb 20260.01512
4 Feb 20260.00903
1 Mar 20260.01389
4 Mar 20260.00903
14 Apr 20260.01017
1 May 20260.00903
12 Jun 20260.00832
15 Jun 20260.06283
22 Jun 20260.06358
23 Jun 20260.0642
28 Aug 20260.06358

78 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 0.06358Published2020-09-27Index as of2026-08-28

Exploit probability more than doubled between 2025-07-30 and 2025-08-01 (0.00579 → 0.0125) and the record had been public for 5 years, 11 months when this index was last written.

Published 2020-09-27 receipt · Index as of 2026-08-28 derived

The pattern, elsewhere

This record is one instance of CWE-74, improper neutralization of special elements in output used by a downstream component ('injection'). The index holds 5545 prior instances of this class, 13 KEV-listed. The nearest of its KEV-listed records are drawn beside this. [email protected]

CVE-2023-22527 · Atlassian Confluence Data Centermatches 5 of 8KEV listed · 2024receipt
CVE-2022-27924matches 5 of 8KEV listed · 2022receipt
CVE-2025-20281 · Cisco Identity Services Engine Softwarematches 5 of 8KEV listed · 2025receipt
CVE-2025-20337 · Cisco Identity Services Engine Softwarematches 5 of 8KEV listed · 2025receipt
CVE-2019-2725 · Oracle Corporation Tape Library ACSLSmatches 4 of 8KEV listed · 2019receipt
CVE-2022-35914matches 4 of 8KEV listed · 2022receipt

"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

5545 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.

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