CVE-2026-100890

MEDIUMPre-NVD 5.35.3—
EchelonGraph scoreHIGH confidence

Score 5.3 from GitHub Security Advisory published 2026-09-28. A secondary CVSS source baseline 5.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 5 sources updated this weekElevated
5.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.4%CVSS: 5.3Exploit: Elevated riskExposed services: Not assessed

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

A flaw has been found in Trusted Domain Project OpenDMARC up to 1.4.2. Affected by this vulnerability is the function opendmarc_spf_ipv6_explode in the library libopendmarc/opendmarc_spf.c of the component SPF Parser. This manipulation of the argument cp causes null pointer dereference. It is possible to initiate the attack remotely. The exploit has been published and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

CVSS v3
5.3
EG Score
5.3MEDIUMhigh confidence
EG Risk
55
EG Risk 55/100CISA SSVC

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
Severity53% × 45%
Exploitation40% × 40%
Automatability100% × 15%
CISA SSVC: Track at low or medium mission impact; Attend at high (mission-essential systems).
Action: No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and watch the vendor's advisory for the fix.
EPSS PROB
0.4%
EPSS %ILE
28th
KEV
Not listed

CISA SSVCTrack at low or medium mission impact; Attend at high (mission-essential systems).

No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and watch the vendor's advisory for the fix.

Exploitation public PoC (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

September 28, 2026

Last Modified

September 28, 2026

Advisory Details (1)

Auto-updated Sep 28, 2026
🔬 Proof of concept available. No patch confirmed yet.
generic🟡 PoC Available

OpenDMARC wild-pointer dereference in opendmarc_spf_ipv6_explode() via a malformed ip6: mechanism (OpenDMARC ≤ 1.4.2; latest version tested 2026-07-30)

https://weitongli.com/share/opendmarc-ip6-wild-pointer.html

Vendor Advisories for CVE-2026-100890(1)

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

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 27× in last 7d / 27× 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. 2026-10-03 14:25 UTCEPSS rescore
  2. 2026-10-03 13:44 UTCEG score recompute
  3. 2026-10-03 13:44 UTCGHSA enrichment
  4. 2026-10-02 14:02 UTCEG score recompute
  5. 2026-10-02 14:02 UTCGHSA enrichment
  6. 2026-10-01 19:49 UTCEPSS rescore
  7. 2026-10-01 14:24 UTCEG score recompute
  8. 2026-10-01 14:24 UTCGHSA enrichment
  9. 2026-09-30 15:02 UTCEPSS rescore
  10. 2026-09-30 14:46 UTCEG score recompute
  11. 2026-09-30 14:45 UTCGHSA enrichment
  12. 2026-09-29 15:20 UTCEPSS rescore
  13. 2026-09-29 15:08 UTCEG score recompute
  14. 2026-09-29 15:07 UTCGHSA enrichment
  15. 2026-09-28 15:29 UTCEG score recompute
  16. 2026-09-28 15:29 UTCGHSA enrichment
  17. 2026-09-28 13:50 UTCEPSS rescore
  18. 2026-09-28 13:29 UTCEG score recompute
  19. 2026-09-28 13:29 UTCGHSA enrichment
  20. 2026-09-28 13:29 UTCNVD updateCVSS v4 → 5.5
  21. 2026-09-28 13:07 UTCEG score recompute
  22. 2026-09-28 13:07 UTCGHSA enrichment
  23. 2026-09-28 13:07 UTCMITRE cvelistV5CVSS v4 → 6.9
  24. 2026-09-28 01:20 UTCEG score recompute
  25. 2026-09-28 01:19 UTCNVD updateCVSS v4 → 5.5
Show 2 more
  1. 2026-09-28 00:48 UTCEG score recompute
  2. 2026-09-28 00:47 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-100890?
CVE-2026-100890 is a medium vulnerability published on September 28, 2026. A flaw has been found in Trusted Domain Project OpenDMARC up to 1.4.2. Affected by this vulnerability is the function opendmarcspfipv6explode in the library libopendmarc/opendmarcspf.c of the component SPF Parser. This manipulation of the argument cp causes null pointer dereference. It is possible…
When was CVE-2026-100890 disclosed?
CVE-2026-100890 was first published on September 28, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-100890 actively exploited?
CVE-2026-100890 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.4% probability of exploitation in the next 30 days (28th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-100890?
CVE-2026-100890 has a CVSS base score of 5.3 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-100890?
No fix for CVE-2026-100890 is confirmed yet. Until one is published, restrict network exposure of the affected system or apply the vendor's mitigation — for example, keep it off the internet or limit it to trusted networks — and watch the vendor's advisory for the fix. The vendor advisories EchelonGraph has for CVE-2026-100890 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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