CVE-2026-53508

MEDIUMPre-NVD 6.06.0
EchelonGraph scoreMEDIUM confidence

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

This medium-severity CVE scores 6.0 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.5% (41st 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
6.0EG
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: 0.5%CVSS: 6.0Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

oasdiff is a command-line and Go package that compares and detects breaking changes in OpenAPI specs. From version 1.13.2 through version 1.18.0, oasdiff did not enforce --allow-external-refs=false (library: openapi3.Loader.IsExternalRefsAllowed = false) when loading a spec from a git revision (the rev:path form, e.g. main:openapi.yaml). External $refs were resolved on that load path even when external refs were explicitly disabled, so the mitigation silently did not apply there. This issue has been patched in version 1.18.1.

CVSS v3
6.0
EG Score
6.0MEDIUMmedium confidence
EG Risk
27
EG Risk 27/100

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 (value × EchelonGraph’s weight)
Severity60% × 45%
The EG Score, 6.0 of 10.
Exploitation0.5% × 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
0.5%
EPSS %ILE
41st
KEV
Not listed

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.

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

July 7, 2026

Last Modified

September 9, 2026

Advisory Details (4)

Auto-updated Aug 31, 2026
Patch available. Sources: github, github_pr.
GitHub pull request

load: typed ExternalRefError + dedicated exit code 123

Fix merged in oasdiff/oasdiff PR #975 on 2026-05-30 — awaiting tagged release

https://github.com/oasdiff/oasdiff/pull/975
GitHub pull request

fix: honor --allow-external-refs on the git-revision load path

Fix merged in oasdiff/oasdiff PR #974 on 2026-05-30 — awaiting tagged release

https://github.com/oasdiff/oasdiff/pull/974
GitHub pull request

fix: resolve $ref chains via git show when loading from git revision specs

Fix merged in oasdiff/oasdiff PR #832 on 2026-04-09 — awaiting tagged release

https://github.com/oasdiff/oasdiff/pull/832
GitHub advisoryMentions a patch (unverified)

oasdiff does not enforce --allow-external-refs=false on the git-revision load path (SSRF / local file read) · Advisory · oasdiff/oasdiff · GitHub

https://github.com/oasdiff/oasdiff/security/advisories/GHSA-2jcc-mxv7-p3f9

Vendor Advisories for CVE-2026-53508(1)

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

Affected Packages

(1 across 1 ecosystem)
Go(1)
PackageVulnerable rangeFix by version rangeDependents
github.com/oasdiff/oasdiff—
  • 1.13.2 up to 1.18.1: fixed in 1.18.1
—

Weakness Classification(3)

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

Data Freshness Timeline

(refreshed 11× in last 7d / 32× 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.

  1. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  2. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  3. 2026-10-12 15:57 UTCEG score recompute
  4. 2026-10-11 19:40 UTCEG score recompute
  5. 2026-10-11 16:55 UTCEG score recompute
  6. 2026-10-11 14:19 UTCEG score recompute
  7. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  8. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  9. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  10. 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  11. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  12. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  13. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  14. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  15. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  16. 2026-10-02 17:56 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  17. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  18. 2026-10-01 16:24 UTCEG score recompute
  19. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  20. 2026-09-29 15:22 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  21. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  22. 2026-09-28 13:34 UTCEG score recompute
  23. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  24. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  25. 2026-09-24 14:04 UTCEPSS rescoreEPSS 0.5% · 40th percentile
Show 28 more
  1. 2026-09-23 17:54 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  2. 2026-09-23 06:15 UTCEG score recompute
  3. 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  4. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  5. 2026-09-18 05:48 UTCEG score recompute
  6. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  7. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  8. 2026-09-14 07:02 UTCEG score recompute
  9. 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  10. 2026-09-13 08:29 UTCEG score recompute
  11. 2026-09-12 03:41 UTCEG score recompute
  12. 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  13. 2026-09-10 09:35 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  14. 2026-09-09 22:57 UTCEG score recompute
  15. 2026-09-08 22:01 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  16. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  17. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.3% · 21st percentile
  18. 2026-09-05 22:52 UTCEG score recompute
  19. 2026-09-04 05:06 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  20. 2026-09-02 14:12 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  21. 2026-09-01 13:54 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  22. 2026-08-31 19:35 UTCEG score recompute
  23. 2026-08-31 18:55 UTCEG score recomputeFirst assessed: 6.0 MEDIUM
  24. 2026-08-31 18:54 UTCMITRE cvelistV5CVSS v3 → 6 · CVSS v4 → 6
  25. 2026-08-02 01:23 UTCEG score recompute
  26. 2026-07-26 12:34 UTCEG score recompute
  27. 2026-07-23 03:19 UTCEG score recompute
  28. 2026-07-08 00:12 UTCEG score recompute

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-53508?
CVE-2026-53508 is a medium-severity vulnerability; its CVE record was published on July 7, 2026. oasdiff is a command-line and Go package that compares and detects breaking changes in OpenAPI specs. From version 1.13.2 through version 1.18.0, oasdiff did not enforce --allow-external-refs=false (library: openapi3.Loader.IsExternalRefsAllowed = false) when loading a spec from a git revision (the…
When was the CVE record for CVE-2026-53508 published?
The CVE record for CVE-2026-53508 was published on July 7, 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 September 9, 2026; the record at its source may have been updated since.
Is CVE-2026-53508 actively exploited?
CVE-2026-53508 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.5% probability of exploitation in the next 30 days (41st percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-53508?
CVE-2026-53508 has a CVSS base score of 6.0 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-53508?
A fix for CVE-2026-53508 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-53508 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-53508

Explore →

Is Your Infrastructure Affected by CVE-2026-53508?

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

Book a Demo →Browse All CVEs