CVE-2026-53537

MEDIUMNVD 5.35.3—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.3 under NVD CVSS v3. EPSS exploit probability: 0.2%, top 93% 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, nvd
5.3
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 5.3Exploit: NoneExposed: 0

A fix is available — apply it.

Python-Multipart is a streaming multipart parser for Python. Prior to 0.0.30, parse_options_header parsed Content-Disposition (and Content-Type) headers with email.message.Message, which transparently applies RFC 2231/5987 decoding. The extended parameter syntax (filename*=charset'lang'value, name*=..., and the filename*0/filename*1 continuation form) is decoded and surfaced under the bare filename/name key, and overrides the plain parameter when both are present. RFC 7578 §4.2 explicitly forbids the filename* form in multipart/form-data. Components that follow RFC 7578, or that do not implement RFC 2231/5987 decoding for multipart/form-data (WAFs, proxies, gateways), may interpret such a header differently. An attacker can exploit that difference to smuggle a different field name or filename past an upstream inspector to the backend. This vulnerability is fixed in 0.0.30.

CVSS v3
5.3
EG Score
5.3(medium)
EG Risk
—
EPSS
7.5%
KEV
Not listed

Published

June 15, 2026

Last Modified

June 26, 2026

Advisory Details (1)

Auto-updated Jun 26, 2026
Patch available. Sources: github.
github Patch Available

Content-Disposition parameter smuggling via RFC 2231/5987 extended parameters · Advisory · Kludex/python-multipart · GitHub

https://github.com/Kludex/python-multipart/security/advisories/GHSA-vffw-93wf-4j4q

Vendor Advisories for CVE-2026-53537(1)

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

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatjaeger-main-2.19.0-1.hum12026-06-10redhat

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

(1 across 1 ecosystem)
PyPI(1)
PackageVulnerable rangeFixed inDependents
python-multipart0.0.1 ... 0.0.9 (29 versions)0.0.30—

Weakness Classification(2)

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

All Vendor Advisories

(1)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 8× in last 7d / 49× 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. 2026-07-22 14:08 UTCEPSS rescore
  2. 2026-07-21 15:25 UTCEPSS rescore
  3. 2026-07-20 17:08 UTCEPSS rescore
  4. 2026-07-19 14:31 UTCEPSS rescore
  5. 2026-07-19 14:31 UTCEPSS rescore
  6. 2026-07-19 02:29 UTCEPSS rescore
  7. 2026-07-18 10:04 UTCEPSS rescore
  8. 2026-07-16 17:03 UTCEPSS rescore
  9. 2026-07-15 16:57 UTCEPSS rescore
  10. 2026-07-15 16:57 UTCEPSS rescore
  11. 2026-07-15 16:05 UTCVendor advisory
  12. 2026-07-15 02:00 UTCEPSS rescore
  13. 2026-07-15 02:00 UTCEPSS rescore
  14. 2026-07-14 17:21 UTCVendor advisory
  15. 2026-07-13 22:31 UTCEPSS rescore
  16. 2026-07-13 18:31 UTCVendor advisory
  17. 2026-07-13 06:13 UTCEPSS rescore
  18. 2026-07-13 06:13 UTCEPSS rescore
  19. 2026-07-12 05:46 UTCEPSS rescore
  20. 2026-07-11 08:27 UTCEPSS rescore
  21. 2026-07-11 08:27 UTCEPSS rescore
  22. 2026-07-09 19:10 UTCEPSS rescore
  23. 2026-07-09 19:10 UTCEPSS rescore
  24. 2026-07-08 15:16 UTCEPSS rescore
  25. 2026-07-08 15:16 UTCEPSS rescore
Show 25 more
  1. 2026-07-07 13:46 UTCEPSS rescore
  2. 2026-07-07 13:46 UTCEPSS rescore
  3. 2026-07-06 16:27 UTCEPSS rescore
  4. 2026-07-06 16:27 UTCEPSS rescore
  5. 2026-07-06 02:23 UTCEPSS rescore
  6. 2026-07-06 02:23 UTCEPSS rescore
  7. 2026-07-05 02:31 UTCEPSS rescore
  8. 2026-07-05 02:30 UTCEPSS rescore
  9. 2026-07-04 06:31 UTCEPSS rescore
  10. 2026-07-04 06:31 UTCEPSS rescore
  11. 2026-07-01 15:07 UTCEPSS rescore
  12. 2026-06-30 23:22 UTCEPSS rescore
  13. 2026-06-29 14:06 UTCEPSS rescore
  14. 2026-06-29 14:06 UTCEPSS rescore
  15. 2026-06-28 14:07 UTCEPSS rescore
  16. 2026-06-28 04:56 UTCEPSS rescore
  17. 2026-06-28 04:56 UTCEPSS rescore
  18. 2026-06-27 19:46 UTCEG score recompute▲ 1.60
  19. 2026-06-27 03:08 UTCEPSS rescore
  20. 2026-06-26 21:42 UTCNVD updateCVSS v3 → 5.3 · severity → MEDIUM
  21. 2026-06-25 13:49 UTCEPSS rescore
  22. 2026-06-24 14:05 UTCEPSS rescore
  23. 2026-06-23 21:33 UTCEPSS rescore
  24. 2026-06-23 21:33 UTCEPSS rescore
  25. 2026-06-15 20:46 UTCEG score recompute

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-53537?
CVE-2026-53537 is a medium vulnerability published on June 15, 2026. Python-Multipart is a streaming multipart parser for Python. Prior to 0.0.30, parseoptionsheader parsed Content-Disposition (and Content-Type) headers with email.message.Message, which transparently applies RFC 2231/5987 decoding. The extended parameter syntax (filename=charset'lang'value,…
When was CVE-2026-53537 disclosed?
CVE-2026-53537 was first published in the National Vulnerability Database on June 15, 2026, with the most recent update on June 26, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-53537 actively exploited?
CVE-2026-53537 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 7.5% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-53537?
CVE-2026-53537 has a CVSS v3 base score of 5.3 (NVD).
How do I remediate CVE-2026-53537?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-53537, 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

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