CVE-2026-0864

MEDIUMNVD 5.55.5—
EchelonGraph scoreMEDIUM confidence

Score 5.5 from GitHub Security Advisory published 2026-06-23. NVD baseline CVSS 5.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Trending — 4 sources updated this week
5.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.5Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

When using the "configparser" module to write configuration files containing multi-line text values with carriage return characters (\r) the resulting file could be injected with unexpected keys and values if the attacker controls the written value.

CVSS v3
5.5
EG Score
5.5(medium)
EG Risk
25(Track)
EG Risk 25/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity55% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
3%
KEV
Not listed

Published

June 23, 2026

Last Modified

August 18, 2026

Advisory Details (7)

Auto-updated Jun 25, 2026
Upstream fix merged — awaiting tagged release. Sources: github_commit, github_pr.
generic

Mailman 3 [CVE-2026-0864] Configparser newline injection in write() method - Security-announce - python.org

https://mail.python.org/archives/list/[email protected]/thread/CV4NE6AFCRJL7XQOHX7J5TSDHUWVWGJS/
github_pr

gh-151558: Fix symlink escape via `tarfile` hardlink-extraction fallback

Fix merged in python/cpython PR #151559 on 2026-06-23 — awaiting tagged release

https://github.com/python/cpython/pull/151559
generic

Normalize all line ending (CR, CRLF, and LF) to LF+TAB in configparser · Issue #143927 · python/cpython · GitHub

https://github.com/python/cpython/issues/143927
github_commit

commit aaf850fd333c (python/cpython)

Fix landed in python/cpython commit aaf850fd333c — awaiting tagged release

https://github.com/python/cpython/commit/aaf850fd333cd89e9aada03d92aaa788a6cb1bb8
github_commit

commit 71f2e02a52d4 (python/cpython)

Fix landed in python/cpython commit 71f2e02a52d4 — awaiting tagged release

https://github.com/python/cpython/commit/71f2e02a52d47417a6fd69f456346cd8aa7aca98
github_commit

commit 5858e42c539d (python/cpython)

Fix landed in python/cpython commit 5858e42c539d — awaiting tagged release

https://github.com/python/cpython/commit/5858e42c539dac8394636a6e9b30472b8994851f
github_commit

commit 0adb386f6e68 (python/cpython)

Fix landed in python/cpython commit 0adb386f6e68 — awaiting tagged release

https://github.com/python/cpython/commit/0adb386f6e68eb2e73d32e19f235d012df009528

Vendor Advisories for CVE-2026-0864(2)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(10 across 4 ecosystems)
Debian:11(3)
PackageVulnerable rangeFixed inDependents
pypy37.3.10+dfsg-1 ... 7.3.9+dfsg-5 (53 versions)——
python2.72.7.18-10 ... 2.7.18-9 (10 versions)——
python3.93.9.10-1 ... 3.9.9-4 (29 versions)——
Debian:14(3)
PackageVulnerable rangeFixed inDependents
pypy37.3.19+dfsg-2 ... 7.3.23+dfsg-1 (11 versions)——
python3.133.13.11-1 ... 3.13.9-1 (8 versions)——
python3.143.14.0-1 ... 3.14.6-1 (24 versions)——
Debian:12(2)
PackageVulnerable rangeFixed inDependents
pypy37.3.11+dfsg-2 ... 7.3.23+dfsg-1 (29 versions)——
python3.113.11.2-6 ... 3.11.9-1 (28 versions)——
Debian:13(2)
PackageVulnerable rangeFixed inDependents
pypy37.3.19+dfsg-2 ... 7.3.23+dfsg-1 (11 versions)——
python3.133.13.11-1 ... 3.13.9-1 (12 versions)——

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 10× in last 7d / 92× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 171 total refreshes for this CVE.

  1. 2026-08-30 01:21 UTCEPSS rescore
  2. 2026-08-28 21:40 UTCEPSS rescore
  3. 2026-08-27 14:24 UTCEPSS rescore
  4. 2026-08-25 13:48 UTCEPSS rescore
  5. 2026-08-24 13:59 UTCEG score recompute
  6. 2026-08-24 13:59 UTCVendor advisory
  7. 2026-08-24 13:59 UTCGHSA enrichment
  8. 2026-08-23 13:53 UTCEG score recompute
  9. 2026-08-23 13:53 UTCVendor advisory
  10. 2026-08-23 13:53 UTCGHSA enrichment
  11. 2026-08-23 00:19 UTCEPSS rescore
  12. 2026-08-22 13:46 UTCEG score recompute
  13. 2026-08-22 13:46 UTCVendor advisory
  14. 2026-08-22 13:46 UTCGHSA enrichment
  15. 2026-08-21 23:48 UTCEPSS rescore
  16. 2026-08-21 07:51 UTCEG score recompute
  17. 2026-08-21 07:51 UTCVendor advisory
  18. 2026-08-21 07:51 UTCGHSA enrichment
  19. 2026-08-20 22:55 UTCEPSS rescore
  20. 2026-08-20 07:45 UTCEG score recompute
  21. 2026-08-20 07:45 UTCVendor advisory
  22. 2026-08-20 07:45 UTCGHSA enrichment
  23. 2026-08-19 17:03 UTCEPSS rescore
  24. 2026-08-18 18:05 UTCEG score recompute▲ 1.40
  25. 2026-08-18 18:05 UTCVendor advisory
Show 75 more
  1. 2026-08-18 18:05 UTCGHSA enrichment
  2. 2026-08-18 18:01 UTCNVD updateCVSS v3 → 5.5
  3. 2026-08-18 13:48 UTCEPSS rescore
  4. 2026-08-17 01:44 UTCEG score recompute
  5. 2026-08-17 01:44 UTCVendor advisory
  6. 2026-08-17 01:44 UTCGHSA enrichment
  7. 2026-08-16 14:56 UTCEPSS rescore
  8. 2026-08-16 02:14 UTCEPSS rescore
  9. 2026-08-16 01:39 UTCVendor advisory
  10. 2026-08-16 01:39 UTCGHSA enrichment
  11. 2026-08-15 01:33 UTCEG score recompute
  12. 2026-08-15 01:33 UTCVendor advisory
  13. 2026-08-15 01:33 UTCGHSA enrichment
  14. 2026-08-15 01:30 UTCEPSS rescore
  15. 2026-08-14 01:28 UTCEG score recompute
  16. 2026-08-14 01:28 UTCVendor advisory
  17. 2026-08-14 01:28 UTCGHSA enrichment
  18. 2026-08-13 22:00 UTCEPSS rescore
  19. 2026-08-13 01:23 UTCEG score recompute
  20. 2026-08-13 01:23 UTCGHSA enrichment
  21. 2026-08-13 00:41 UTCEG score recompute
  22. 2026-08-13 00:41 UTCGHSA enrichment
  23. 2026-08-12 13:50 UTCEPSS rescore
  24. 2026-08-12 01:27 UTCEG score recompute
  25. 2026-08-12 01:27 UTCGHSA enrichment
  26. 2026-08-11 13:42 UTCEPSS rescore
  27. 2026-08-11 01:22 UTCEG score recompute
  28. 2026-08-11 01:22 UTCGHSA enrichment
  29. 2026-08-11 00:34 UTCEG score recompute
  30. 2026-08-11 00:34 UTCGHSA enrichment
  31. 2026-08-10 23:59 UTCEPSS rescore
  32. 2026-08-10 01:42 UTCEG score recompute
  33. 2026-08-10 01:42 UTCGHSA enrichment
  34. 2026-08-09 13:46 UTCEPSS rescore
  35. 2026-08-09 01:36 UTCEG score recompute
  36. 2026-08-09 01:36 UTCGHSA enrichment
  37. 2026-08-08 16:37 UTCEPSS rescore
  38. 2026-08-08 01:31 UTCEG score recompute
  39. 2026-08-08 01:31 UTCGHSA enrichment
  40. 2026-08-07 01:26 UTCEG score recompute
  41. 2026-08-07 01:26 UTCGHSA enrichment
  42. 2026-08-06 13:46 UTCEPSS rescore
  43. 2026-08-06 01:21 UTCEG score recompute
  44. 2026-08-06 01:21 UTCGHSA enrichment
  45. 2026-08-06 00:50 UTCEG score recompute
  46. 2026-08-06 00:50 UTCGHSA enrichment
  47. 2026-08-05 19:17 UTCEPSS rescore
  48. 2026-08-05 14:28 UTCEG score recompute
  49. 2026-08-05 14:28 UTCGHSA enrichment
  50. 2026-08-05 13:49 UTCEG score recompute
  51. 2026-08-05 13:49 UTCGHSA enrichment
  52. 2026-08-05 01:19 UTCEG score recompute
  53. 2026-08-05 01:19 UTCGHSA enrichment
  54. 2026-08-05 00:51 UTCEG score recompute
  55. 2026-08-05 00:51 UTCGHSA enrichment
  56. 2026-08-04 15:14 UTCEG score recompute
  57. 2026-08-04 15:14 UTCGHSA enrichment
  58. 2026-08-04 15:09 UTCEPSS rescore
  59. 2026-08-04 10:38 UTCEPSS rescore
  60. 2026-08-03 10:35 UTCEPSS rescore
  61. 2026-08-03 09:32 UTCGHSA enrichment
  62. 2026-08-02 09:20 UTCEG score recompute
  63. 2026-08-02 09:20 UTCGHSA enrichment
  64. 2026-08-02 02:26 UTCEPSS rescore
  65. 2026-08-01 09:15 UTCEG score recompute
  66. 2026-08-01 09:15 UTCGHSA enrichment
  67. 2026-08-01 04:15 UTCEPSS rescore
  68. 2026-07-31 09:10 UTCEG score recompute
  69. 2026-07-31 09:10 UTCGHSA enrichment
  70. 2026-07-30 16:27 UTCEPSS rescore
  71. 2026-07-30 08:58 UTCEG score recompute
  72. 2026-07-30 08:58 UTCGHSA enrichment
  73. 2026-07-30 01:30 UTCEPSS rescore
  74. 2026-07-29 06:26 UTCEG score recompute
  75. 2026-07-29 06:26 UTCGHSA enrichment

Frequently asked(5)

What is CVE-2026-0864?
CVE-2026-0864 is a medium vulnerability published on June 23, 2026. When using the "configparser" module to write configuration files containing multi-line text values with carriage return characters (\r) the resulting file could be injected with unexpected keys and values if the attacker controls the written value.
When was CVE-2026-0864 disclosed?
CVE-2026-0864 was first published in the National Vulnerability Database on June 23, 2026, with the most recent update on August 18, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-0864 actively exploited?
CVE-2026-0864 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 97.4% of all scored CVEs.
What is the CVSS score of CVE-2026-0864?
CVE-2026-0864 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2026-0864?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-0864, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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