libgit2 is a portable C implementation of the Git core methods provided as a linkable library with a solid API, allowing to build Git functionality into your application. Prior to 1.8.6 and 1.9.5, git_delta_apply in src/libgit2/delta.c trusts the attacker-controlled res_sz value parsed by hdr_sz from a delta object header and passes that amount to git__malloc before validating delta instructions. Malicious pack data supplied through git_clone, git_fetch, git_remote_fetch, git_indexer_append, or a local attacker-supplied repository can use a very small multi-level OFS_DELTA chain to retain extremely large allocations and exhaust memory. This issue is fixed in versions 1.8.6 and 1.9.5.
CVE-2026-53585
MEDIUMPre-NVD 5.35.3—Trending — Patch released this weekElevated
EchelonGraph scoreMEDIUM confidence
This medium-severity CVE scores 5.3 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 75% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
Triggered by: NVD CVSS baseline
Sources: epss, secondary
5.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
- Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.3Exploit: Elevated riskExposed: 0
A fix is available — apply it.
- CVSS v3
- 5.3
- EG Score
- 5.3(medium)
- EG Risk
- 55(Attend)EG Risk 55/100SSVC: Attend
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 computedSeverity53% × 45%Exploitation40% × 40%Automatability100% × 15%Action: Remediate soon — notable exploitation risk. - EPSS PROB
- 0%
- EPSS %ILE
- 25%
- KEV
- Not listed
Published
August 20, 2026
Last Modified
August 25, 2026
Advisory Details (6)
Auto-updated Aug 20, 2026🔬 Proof of concept available. Patch available. Sources: github, github_commit, github_release.
github_release Patch Available
libgit2 v1.9.5
Patch available: libgit2/libgit2 v1.9.5
https://github.com/libgit2/libgit2/releases/tag/v1.9.5github_release Patch Available
libgit2 v1.8.6
Patch available: libgit2/libgit2 v1.8.6
https://github.com/libgit2/libgit2/releases/tag/v1.8.6github_commit
commit dec22ac01ad9 (libgit2/libgit2)
Fix landed in libgit2/libgit2 commit dec22ac01ad9 — awaiting tagged release
https://github.com/libgit2/libgit2/commit/dec22ac01ad9620c96b7b9ac3ef636ea46d43bedgithub_commit Patch Available
commit c1896f06df22 (libgit2/libgit2)
Patch available: libgit2/libgit2 v1.8.6 (contains commit c1896f06df22)
https://github.com/libgit2/libgit2/commit/c1896f06df22cc0ca5658df3a8f6cd7ede4cd6aegithub_commit Patch Available
commit 0cdfdd5fa8f8 (libgit2/libgit2)
Patch available: libgit2/libgit2 v1.9.5 (contains commit 0cdfdd5fa8f8)
https://github.com/libgit2/libgit2/commit/0cdfdd5fa8f8514c82413025e1e0808866cf7c30github Patch Available🟡 PoC Available
Unbounded Memory Allocation via Delta Object Result-Size Header · Advisory · libgit2/libgit2 · GitHub
https://github.com/libgit2/libgit2/security/advisories/GHSA-27m5-gxxh-x79jVendor Advisories for CVE-2026-53585(1)
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 / Ecosystem | Fixed in / Patch | Released | Source |
|---|---|---|---|
| redhat | libgit2-main-1.9.7-1.hum1 | 2026-08-25 | redhat |
| ubuntu | libgit2-fixtures (1.9.1+ds-1ubuntu1.1) @ resolute | 2026-08-25 | ubuntu |
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.
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Additional Vendor Advisories
(1)
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 19× in last 7d / 19× 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.
- 2026-08-25 16:26 UTCEG score recompute
- 2026-08-25 16:26 UTCVendor advisory
- 2026-08-25 15:30 UTCEG score recompute
- 2026-08-25 15:30 UTCVendor advisory
- 2026-08-25 13:49 UTCEPSS rescore
- 2026-08-24 22:24 UTCEG score recompute
- 2026-08-24 22:24 UTCVendor advisory
- 2026-08-23 21:38 UTCEG score recompute
- 2026-08-23 21:38 UTCVendor advisory
- 2026-08-23 00:19 UTCEPSS rescore
- 2026-08-22 20:52 UTCEG score recompute
- 2026-08-22 20:52 UTCVendor advisory
- 2026-08-21 23:49 UTCEPSS rescore
- 2026-08-21 20:05 UTCVendor advisory
- 2026-08-20 19:18 UTCEG score recompute
- 2026-08-20 19:18 UTCVendor advisory
- 2026-08-20 18:52 UTCEG score recompute
- 2026-08-20 18:52 UTCVendor advisory
- 2026-08-20 18:51 UTCMITRE cvelistV5first tracked
Frequently asked(5)
What is CVE-2026-53585?
CVE-2026-53585 is a medium vulnerability published on August 20, 2026. libgit2 is a portable C implementation of the Git core methods provided as a linkable library with a solid API, allowing to build Git functionality into your application. Prior to 1.8.6 and 1.9.5, gitdeltaapply in src/libgit2/delta.c trusts the attacker-controlled ressz value parsed by hdrsz from a…
When was CVE-2026-53585 disclosed?
CVE-2026-53585 was first published in the National Vulnerability Database on August 20, 2026, with the most recent update on August 25, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-53585 actively exploited?
CVE-2026-53585 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 74.7% of all scored CVEs.
What is the CVSS score of CVE-2026-53585?
CVE-2026-53585 has a CVSS v3 base score of 5.3 (NVD).
How do I remediate CVE-2026-53585?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-53585, 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-2026-53585
Is Your Infrastructure Affected by CVE-2026-53585?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.