CVE-2026-6019

MEDIUMNVD 6.16.1
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to NVD's CVSS score.

Score 6.1 from GitHub Security Advisory (severity: LOW) published 2026-04-22. NVD baseline CVSS 6.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, NVD CVSS v3
Trending — 4 sources updated this week

Also known asEUVD-2026-25079 (ENISA EUVD) · GHSA-2755-2mm4-rm5c (GitHub Security Advisories)Source: ENISA EUVD

6.1EG
EchelonGraph verdictMonitorRemediate within your standard update timelines (the SSVC decision on this page).
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.2%CVSS: 6.1Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

http.cookies.Morsel.js_output() returns an inline snippet and only escapes " for JavaScript string context. It does not neutralize the HTML parser-sensitive sequence inside the generated script element. Mitigation base64-encodes the cookie value to disallow escaping using cookie value.

CVSS v3
6.1
EG Score
6.1MEDIUMmedium confidence
EG Risk
28
EG Risk 28/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity61% × 45%
Impact severity (EG Severity): CVSS 6.1 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.2% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at every mission impact level.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it within your standard update timelines.
EPSS PROB
0.2%
EPSS %ILE
11th
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (6.1): severity, escalated by confirmed exploitation. This CVE's 6.1 is its impact severity (EG Severity), not escalated.

EG Severity
6.1 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-29). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.

A fix is available. Apply it within your standard update timelines.

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

April 22, 2026

Last Modified

October 26, 2026

Advisory Details (6)

Auto-updated Jul 27, 2026
Patch available. Sources: github_commit, github_pr.
Web page

Mailman 3 [CVE-2026-6019] BaseCookie.js_output() does not neutralize characters in cookie value embedded in JS - Security-announce - python.org

https://mail.python.org/archives/list/security-announce@python.org/thread/IVNWGV2BBNC3RHQAFS22UP4DY56SAXX3/
GitHub pull request

gh-90309: Base64-encode cookie values embedded in JS

Fix merged in python/cpython PR #148848 on 2026-04-22 — awaiting tagged release

https://github.com/python/cpython/pull/148848
Web page

SimpleCookie.js_output is vulnerable to HTML injection · Issue #90309 · python/cpython · GitHub

https://github.com/python/cpython/issues/90309
GitHub commit

commit f795e042043d (python/cpython)

Fix landed in python/cpython commit f795e042043d — awaiting tagged release

https://github.com/python/cpython/commit/f795e042043dfe26c42e1971d4502c1cdc4c65b8
GitHub commit

commit 76b3923d688c (python/cpython)

Fix landed in python/cpython commit 76b3923d688c — awaiting tagged release

https://github.com/python/cpython/commit/76b3923d688c0efc580658476c5f525ec8735104
GitHub commit

commit 3c59b8b53fc7 (python/cpython)

Fix landed in python/cpython commit 3c59b8b53fc7 — awaiting tagged release

https://github.com/python/cpython/commit/3c59b8b53fc75c7f9578d16fb8201ceb43e8f76c

Patch Availability(10)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
ubuntupython3.12-venv (3.12.3-1ubuntu0.15) @ noble2026-10-29ubuntu
ubuntupython3.5-venv (3.5.2-2ubuntu0~16.04.13+esm25) @ xenial2026-10-29ubuntu
redhatpython3-12-main-3.12.14-1.hum12026-08-21redhat
redhatpython3-11-main-3.11.16-1.hum12026-08-20redhat
redhatpython3-11-main-3.11.15-4.3.hum12026-06-30redhat
redhatpython3-12-main-3.12.13-3.2.hum12026-06-29redhat
redhatpython3-13-main-3.13.14-1.1.hum12026-06-29redhat
redhatpython3.14-0:3.14.5-1.el10_22026-06-24redhat
redhatpython3.14-0:3.14.5-1.el9_82026-06-23redhat
redhatpython3-14-main-3.14.5-2.hum12026-06-03redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(9 across 4 ecosystems)
Debian:14(3)
PackageVulnerable rangeFix by version rangeDependents
pypy37.3.19+dfsg-2 ... 8.0.0+dfsg-1 (13 versions)
  • every version on: no fix on record
—
python3.133.13.11-1 ... 3.13.9-1 (7 versions)
  • every version up to 3.13.14-1: fixed in 3.13.14-1
—
python3.143.14.0-1 ... 3.14.4-2 (21 versions)
  • every version up to 3.14.5~rc1-1: fixed in 3.14.5~rc1-1
—
Debian:11(2)
PackageVulnerable rangeFix by version rangeDependents
pypy37.3.10+dfsg-1 ... 7.3.9+dfsg-5 (53 versions)
  • every version on: no fix on record
—
python3.93.9.10-1 ... 3.9.9-4 (29 versions)
  • every version on: no fix on record
—
Debian:12(2)
PackageVulnerable rangeFix by version rangeDependents
pypy37.3.11+dfsg-2 ... 8.0.0+dfsg-1 (31 versions)
  • every version on: no fix on record
—
python3.113.11.2-6 ... 3.11.2-6+deb12u8 (9 versions)
  • every version up to 3.11.2-6+deb12u9: fixed in 3.11.2-6+deb12u9
—
Debian:13(2)
PackageVulnerable rangeFix by version rangeDependents
pypy37.3.19+dfsg-2 ... 8.0.0+dfsg-1 (13 versions)
  • every version on: no fix on record
—
python3.133.13.5-2, 3.13.5-2+deb13u1
  • every version up to 3.13.5-2+deb13u2: fixed in 3.13.5-2+deb13u2
—

Weakness Classification(2)

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

Additional Vendor Advisories

(2)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 13× in last 7d / 46× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

Showing the most recent 98 of 246 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. 2 repeat rows among the latest 100 are merged into the row they repeat. The 148 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-01 16:35 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  2. 2026-10-31 16:33 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  3. 2026-10-30 16:35 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  4. 2026-10-29 16:56 UTCEG score recompute
  5. 2026-10-29 16:56 UTCVendor advisory
  6. 2026-10-29 16:56 UTCGHSA enrichmentGHSA-2755-2mm4-rm5c · GitHub severity LOW · GitHub CVSS 6.1
  7. 2026-10-29 16:33 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  8. 2026-10-28 16:33 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  9. 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  10. 2026-10-26 21:54 UTCEG score recompute
  11. 2026-10-26 21:54 UTCVendor advisory
  12. 2026-10-26 21:53 UTCGHSA enrichmentGHSA-2755-2mm4-rm5c · GitHub severity LOW · GitHub CVSS 6.1
  13. 2026-10-26 16:32 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  14. 2026-10-25 16:33 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  15. 2026-10-25 14:15 UTCEG score recompute
  16. 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  17. 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  18. 2026-10-22 20:54 UTCEG score recompute
  19. 2026-10-22 20:54 UTCVendor advisory
  20. 2026-10-22 20:54 UTCGHSA enrichmentGHSA-2755-2mm4-rm5c · GitHub severity LOW · GitHub CVSS 6.1
  21. 2026-10-22 16:35 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  22. 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  23. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  24. 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  25. 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.2% · 10th percentile
Show 73 more
  1. 2026-10-18 03:26 UTCEG score recompute
  2. 2026-10-17 16:35 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  3. 2026-10-16 16:43 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  4. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  5. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  6. 2026-10-13 16:35 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  7. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  8. 2026-10-12 15:52 UTCEG score recompute
  9. 2026-10-11 19:35 UTCEG score recompute
  10. 2026-10-11 16:51 UTCEG score recompute
  11. 2026-10-11 14:13 UTCEG score recompute
  12. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  13. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  14. 2026-10-10 17:25 UTCOSV refresh
  15. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.2% · 10th percentile
  16. 2026-10-08 17:13 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  17. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  18. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  19. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  20. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  21. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  22. 2026-10-02 17:56 UTCEPSS rescoreEPSS 0.6% · 45th percentile
  23. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.6% · 45th percentile
  24. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.6% · 45th percentile
  25. 2026-09-28 13:52 UTCEPSS rescoreEPSS 0.6% · 45th percentile
  26. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.6% · 45th percentile
  27. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.6% · 45th percentile
  28. 2026-09-23 17:54 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  29. 2026-09-21 21:09 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  30. 2026-09-21 04:49 UTCOSV refresh
  31. 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  32. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  33. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  34. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  35. 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  36. 2026-09-11 09:37 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  37. 2026-09-08 22:01 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  38. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  39. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  40. 2026-09-05 15:31 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  41. 2026-09-04 05:07 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  42. 2026-09-02 14:12 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  43. 2026-09-02 02:38 UTCOSV refresh
  44. 2026-09-01 13:54 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  45. 2026-09-01 04:40 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  46. 2026-08-30 19:17 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  47. 2026-08-28 21:42 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  48. 2026-08-26 14:47 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  49. 2026-08-25 13:49 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  50. 2026-08-23 00:19 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  51. 2026-08-21 23:49 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  52. 2026-08-20 22:56 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  53. 2026-08-19 17:04 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  54. 2026-08-18 13:49 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  55. 2026-08-17 13:47 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  56. 2026-08-16 14:56 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  57. 2026-08-16 05:56 UTCEG score recompute
  58. 2026-08-16 05:56 UTCVendor advisory
  59. 2026-08-16 05:56 UTCGHSA enrichmentGHSA-2755-2mm4-rm5c · GitHub severity LOW · GitHub CVSS 6.1
  60. 2026-08-16 02:15 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  61. 2026-08-15 01:30 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  62. 2026-08-14 04:16 UTCEG score recompute
  63. 2026-08-14 04:16 UTCVendor advisory
  64. 2026-08-14 04:16 UTCGHSA enrichmentGHSA-2755-2mm4-rm5c · GitHub severity LOW · GitHub CVSS 6.1
  65. 2026-08-13 22:00 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  66. 2026-08-12 18:27 UTCEG score recompute
  67. 2026-08-12 18:27 UTCVendor advisory
  68. 2026-08-12 18:27 UTCGHSA enrichmentGHSA-2755-2mm4-rm5c · GitHub severity LOW · GitHub CVSS 6.1
  69. 2026-08-12 13:51 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  70. 2026-08-11 05:59 UTCEG score recompute
  71. 2026-08-11 05:59 UTCVendor advisory
  72. 2026-08-11 05:59 UTCGHSA enrichmentGHSA-2755-2mm4-rm5c · GitHub severity LOW · GitHub CVSS 6.1
  73. 2026-08-11 00:00 UTCEPSS rescoreEPSS 0.2% · 13th percentile

Frequently asked(5)

What is CVE-2026-6019?
CVE-2026-6019 is a medium-severity vulnerability; its CVE record was published on April 22, 2026. http.cookies.Morsel.js_output() returns an inline <script> snippet and only escapes " for JavaScript string context. It does not neutralize the HTML parser-sensitive sequence </script> inside the generated script element. Mitigation base64-encodes the cookie value to disallow escaping using cookie…
When was the CVE record for CVE-2026-6019 published?
The CVE record for CVE-2026-6019 was published on April 22, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of October 26, 2026; the record at its source may have been updated since.
Is CVE-2026-6019 actively exploited?
CVE-2026-6019 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.2% probability of exploitation in the next 30 days (11th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-6019?
CVE-2026-6019 has a CVSS v3 base score of 6.1 (NVD).
How do I remediate CVE-2026-6019?
A fix for CVE-2026-6019 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-6019 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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