CVE-2026-49852

HIGHPre-NVD 8.78.7
EchelonGraph scoreMEDIUM confidence

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

This high-severity CVE scores 8.7 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2% (6th percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.

Triggered by: Headline CVSS from a secondary CVSS source
Sources: EPSS, a secondary CVSS source
Trending — 4 sources updated this weekElevated

Also known asEUVD-2026-45281 (ENISA EUVD) · GHSA-gg9x-qcx2-xmrh (GitHub Security Advisories)Source: ENISA EUVD

8.7EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • CISA's Vulnrichment rates exploitation as PoC; EchelonGraph holds no exploit-code reference for it
CISA-KEV: Not listedEPSS PROB: 0.2%CVSS: 8.7Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

joserfc is a Python library that provides an implementation of several JSON Object Signing and Encryption (JOSE) standards. Prior to 1.6.8, joserfc.jwt.decode accepts attacker-forged HMAC-signed tokens when the caller-supplied verification key is the empty string or None, because HMACAlgorithm.sign and HMACAlgorithm.verify in src/joserfc/_rfc7518/jws_algs.py pass the output of OctKey.get_op_key(...) to hmac.new(...) and OctKey.import_key in src/joserfc/_rfc7518/oct_key.py only emits a SecurityWarning for keys shorter than 14 bytes without rejecting zero-length input. This issue is fixed in version 1.6.8.

CVSS v3
8.7
EG Score
8.7HIGHmedium confidence
EG Risk
70
EG Risk 70/100

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)
Severity87% × 45%
Impact severity (EG Severity): CVSS 8.7 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation40% × 40%
EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).
Exploitation public PoC (CISA Vulnrichment) · Automatable yes (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 at low or medium mission impact and sooner than that at high.
EPSS PROB
0.2%
EPSS %ILE
6th
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 (8.7): severity, escalated by confirmed exploitation. This CVE's 8.7 is its impact severity (EG Severity), not escalated.

EG Severity
8.7 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.a secondary CVSS source · CVSS v3.0 or v3.1
EG Likelihood
0.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-31). 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 low or medium mission impact; Attend at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; 60 days 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 low or medium mission impact; Attend at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation public PoC (CISA Vulnrichment) · Automatable yes (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)14 days if the affected system is publicly exposed; 60 days if it is not.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable yes (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

July 2, 2026

Last Modified

October 24, 2026

Advisory Details (3)

Auto-updated Jul 17, 2026
Patch available. Sources: github, github_commit, github_release.
GitHub release Patch Available

1.6.8

Patch available: authlib/joserfc 1.6.8

https://github.com/authlib/joserfc/releases/tag/1.6.8
GitHub commit Patch Available

commit 86d00910b2b2 (authlib/joserfc)

Patch available: authlib/joserfc 1.6.8 (contains commit 86d00910b2b2)

https://github.com/authlib/joserfc/commit/86d00910b2b2d2d07503fee9b572906daefab7f1
GitHub advisoryMentions a patch (unverified)

joserfc: HS256/HS384/HS512 verify accepts empty/nil HMAC key (cross-language sibling of CVE-2026-45363) · Advisory · authlib/joserfc · GitHub

https://github.com/authlib/joserfc/security/advisories/GHSA-gg9x-qcx2-xmrh

Vendor Advisories for CVE-2026-49852(2)

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

Patch Availability(2)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
redhatjaeger-main-2.19.0-1.2.hum12026-07-20redhat
pipjoserfc @ 1.6.8 (fixes <= 1.6.7)—ghsa

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

(3 across 3 ecosystems)
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
joserfc1.1.0-1 ... 1.7.4-1 (22 versions)
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
joserfc1.1.0-1 ... 1.6.5-1 (16 versions)
  • every version up to 1.6.8-1: fixed in 1.6.8-1
—
PyPI(1)
PackageVulnerable rangeFix by version rangeDependents
joserfc0.1.0 ... 1.6.7 (40 versions)
  • every version up to 1.6.8: fixed in 1.6.8
—

Weakness Classification(3)

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

Data Freshness Timeline

(refreshed 11× in last 7d / 47× 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 100 of 174 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. None are among the latest 100 rows. The 74 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-01 16:34 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  2. 2026-11-01 07:46 UTCGHSA enrichmentGHSA-gg9x-qcx2-xmrh · GitHub severity HIGH
  3. 2026-11-01 07:46 UTCEG score recompute
  4. 2026-10-31 16:32 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  5. 2026-10-30 16:34 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  6. 2026-10-29 16:33 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  7. 2026-10-28 16:32 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  8. 2026-10-27 21:01 UTCEG score recompute
  9. 2026-10-27 21:01 UTCVendor advisory
  10. 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  11. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  12. 2026-10-25 16:33 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  13. 2026-10-25 14:22 UTCEG score recompute
  14. 2026-10-24 20:27 UTCEG score recompute
  15. 2026-10-24 20:27 UTCVendor advisory
  16. 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  17. 2026-10-24 10:13 UTCEG score recompute
  18. 2026-10-24 10:13 UTCVendor advisory
  19. 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  20. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  21. 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  22. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  23. 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  24. 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  25. 2026-10-18 03:34 UTCEG score recompute
Show 75 more
  1. 2026-10-17 16:34 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  2. 2026-10-17 11:54 UTCEG score recompute
  3. 2026-10-17 11:54 UTCVendor advisory
  4. 2026-10-16 16:42 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  5. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  6. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  7. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  8. 2026-10-13 14:54 UTCOSV refresh
  9. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  10. 2026-10-12 15:59 UTCEG score recompute
  11. 2026-10-11 19:43 UTCEG score recompute
  12. 2026-10-11 16:57 UTCEG score recompute
  13. 2026-10-11 14:21 UTCEG score recompute
  14. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  15. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  16. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  17. 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  18. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  19. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  20. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  21. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  22. 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  23. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  24. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  25. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  26. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  27. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  28. 2026-09-26 00:27 UTCEPSS rescoreEPSS 0.2% · 8th percentile
  29. 2026-09-23 17:53 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  30. 2026-09-23 06:38 UTCEG score recompute
  31. 2026-09-23 06:38 UTCVendor advisory
  32. 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  33. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  34. 2026-09-18 06:15 UTCEG score recompute
  35. 2026-09-18 06:15 UTCVendor advisory
  36. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  37. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  38. 2026-09-14 00:15 UTCEG score recompute
  39. 2026-09-14 00:15 UTCVendor advisory
  40. 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  41. 2026-09-13 08:59 UTCEG score recompute
  42. 2026-09-13 08:59 UTCVendor advisory
  43. 2026-09-12 14:16 UTCEG score recompute
  44. 2026-09-12 14:16 UTCVendor advisory
  45. 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  46. 2026-09-10 09:35 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  47. 2026-09-08 22:01 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  48. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  49. 2026-09-06 14:19 UTCEG score recompute
  50. 2026-09-06 14:19 UTCVendor advisory
  51. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  52. 2026-09-05 23:53 UTCEG score recompute
  53. 2026-09-05 23:53 UTCVendor advisory
  54. 2026-09-04 05:06 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  55. 2026-09-02 14:12 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  56. 2026-09-01 13:54 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  57. 2026-09-01 04:40 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  58. 2026-08-30 22:43 UTCEG score recompute
  59. 2026-08-30 22:43 UTCVendor advisory
  60. 2026-08-30 19:17 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  61. 2026-08-30 11:22 UTCEG score recompute
  62. 2026-08-30 11:22 UTCVendor advisory
  63. 2026-08-30 01:22 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  64. 2026-08-28 21:41 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  65. 2026-08-27 22:15 UTCEG score recompute
  66. 2026-08-27 22:15 UTCVendor advisory
  67. 2026-08-27 14:25 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  68. 2026-08-26 14:46 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  69. 2026-08-25 13:49 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  70. 2026-08-25 13:43 UTCVendor advisory
  71. 2026-08-24 20:55 UTCEG score recompute
  72. 2026-08-24 20:55 UTCVendor advisory
  73. 2026-08-24 05:30 UTCVendor advisory
  74. 2026-08-23 18:06 UTCVendor advisory
  75. 2026-08-23 06:46 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-49852?
CVE-2026-49852 is a high-severity vulnerability; its CVE record was published on July 2, 2026. joserfc is a Python library that provides an implementation of several JSON Object Signing and Encryption (JOSE) standards. Prior to 1.6.8, joserfc.jwt.decode accepts attacker-forged HMAC-signed tokens when the caller-supplied verification key is the empty string or None, because HMACAlgorithm.sign…
When was the CVE record for CVE-2026-49852 published?
The CVE record for CVE-2026-49852 was published on July 2, 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 24, 2026; the record at its source may have been updated since.
Is CVE-2026-49852 actively exploited?
CVE-2026-49852 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.2% probability of exploitation in the next 30 days (6th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-49852?
CVE-2026-49852 has a CVSS base score of 8.7 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-49852?
A fix for CVE-2026-49852 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-49852 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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