CVE-2026-90679

MEDIUMPre-NVD 4.34.3—
EchelonGraph scoreHIGH confidence

Score 4.3 from GitHub Security Advisory published 2026-09-13. a secondary CVSS source baseline 4.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
4.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 4.3Exploit: None knownExposed: 0

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

Forgejo 13.0.0 through 16.0.4, when "[federation] ENABLED = true" is set, has a spoofing issue that affects identity integrity but does not allow account takeover or content modification. It does not verify that the HTTP Signature on an incoming ActivityPub activity was produced by the key belonging to the actor named in the activity body. The signature verification in routers/api/v1/activitypub/reqsignature.go validates the request signature, but the inbox activity handlers subsequently read the acting identity from the attacker-controlled JSON body without binding it to the verified signing key. Additionally, the signed Digest header is not recomputed against the received request body. A remote attacker who hosts a single valid ActivityPub actor and keypair can therefore submit signature-valid activities attributed to any actor identity they name.

CVSS v3
4.3
EG Score
4.3(high)
EG Risk
19(Track)
EG Risk 19/100SSVC: 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
Severity43% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
6%
KEV
Not listed

Published

September 13, 2026

Last Modified

September 15, 2026

Advisory Details (1)

Auto-updated Sep 13, 2026
No patch confirmed yet.
generic

#14271 - bug: Experimental Security Issue: federation activity spoofing via unbound HTTP signature - forgejo/forgejo - Codeberg.org

https://codeberg.org/forgejo/forgejo/issues/14271#issuecomment-22548004

Vendor Advisories for CVE-2026-90679(1)

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

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 20× in last 7d / 20× 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.

  1. 2026-09-18 19:28 UTCEPSS rescore
  2. 2026-09-18 18:35 UTCGHSA enrichment
  3. 2026-09-17 19:35 UTCEG score recompute
  4. 2026-09-17 19:35 UTCGHSA enrichment
  5. 2026-09-17 19:32 UTCEPSS rescore
  6. 2026-09-16 17:58 UTCEG score recompute
  7. 2026-09-16 17:58 UTCGHSA enrichment
  8. 2026-09-16 14:09 UTCEPSS rescore
  9. 2026-09-16 05:15 UTCEPSS rescore
  10. 2026-09-15 18:35 UTCEG score recompute
  11. 2026-09-15 18:35 UTCGHSA enrichment
  12. 2026-09-15 17:24 UTCEG score recompute
  13. 2026-09-15 17:24 UTCGHSA enrichment
  14. 2026-09-15 03:12 UTCEPSS rescore
  15. 2026-09-15 03:10 UTCGHSA enrichment
  16. 2026-09-14 04:17 UTCEG score recompute
  17. 2026-09-14 04:17 UTCGHSA enrichment
  18. 2026-09-13 04:23 UTCEG score recompute
  19. 2026-09-13 04:02 UTCEG score recompute
  20. 2026-09-13 04:01 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-90679?
CVE-2026-90679 is a medium vulnerability published on September 13, 2026. Forgejo 13.0.0 through 16.0.4, when "[federation] ENABLED = true" is set, has a spoofing issue that affects identity integrity but does not allow account takeover or content modification. It does not verify that the HTTP Signature on an incoming ActivityPub activity was produced by the key…
When was CVE-2026-90679 disclosed?
CVE-2026-90679 was first published in the National Vulnerability Database on September 13, 2026, with the most recent update on September 15, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-90679 actively exploited?
CVE-2026-90679 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 94.1% of all scored CVEs.
What is the CVSS score of CVE-2026-90679?
CVE-2026-90679 has a CVSS v3 base score of 4.3 (NVD).
How do I remediate CVE-2026-90679?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-90679, 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

Explore the affected products and dependency analysis for CVE-2026-90679

Explore →

Is Your Infrastructure Affected by CVE-2026-90679?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs