Skip to content

chore(deps): update dependency python-multipart to v0.0.26 [security]#2571

Open
renovate[bot] wants to merge 1 commit intomainfrom
renovate/pypi-python-multipart-vulnerability
Open

chore(deps): update dependency python-multipart to v0.0.26 [security]#2571
renovate[bot] wants to merge 1 commit intomainfrom
renovate/pypi-python-multipart-vulnerability

Conversation

@renovate
Copy link
Copy Markdown
Contributor

@renovate renovate Bot commented Apr 16, 2026

This PR contains the following updates:

Package Change Age Adoption Passing Confidence
python-multipart (changelog) 0.0.220.0.26 age adoption passing confidence

python-multipart affected by Denial of Service via large multipart preamble or epilogue data

CVE-2026-40347 / GHSA-mj87-hwqh-73pj

More information

Details

Summary

A denial of service vulnerability exists when parsing crafted multipart/form-data requests with large preamble or epilogue sections.

Details

Two inefficient multipart parsing paths could be abused with attacker-controlled input.

Before the first multipart boundary, the parser handled leading CR and LF bytes inefficiently while searching for the start of the first part. After the closing boundary, the parser continued processing trailing epilogue data instead of discarding it immediately. As a result, parsing time could grow with the size of crafted data placed before the first boundary or after the closing boundary.

Impact

An attacker can send oversized malformed multipart bodies that consume excessive CPU time during request parsing, reducing request-handling capacity and delaying legitimate requests. This issue degrades availability but does not typically result in a complete denial of service for the entire application.

Mitigation

Upgrade to version 0.0.26 or later, which skips ahead to the next boundary candidate when processing leading CR/LF data and immediately discards epilogue data after the closing boundary.

Severity

  • CVSS Score: 5.3 / 10 (Medium)
  • Vector String: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

References

This data is provided by OSV and the GitHub Advisory Database (CC-BY 4.0).


Release Notes

Kludex/python-multipart (python-multipart)

v0.0.26

Compare Source

  • Skip preamble before the first multipart boundary more efficiently #​262.
  • Silently discard epilogue data after the closing multipart boundary #​259.

v0.0.25

Compare Source

  • Add MIME content type info to File #​143.
  • Handle CTE values case-insensitively #​258.
  • Remove custom FormParser classes #​257.
  • Add UPLOAD_DELETE_TMP to FormParser config #​254.
  • Emit field_end for trailing bare field names on finalize #​230.
  • Handle multipart headers case-insensitively #​252.
  • Apply Apache-2.0 properly #​247.

v0.0.24

Compare Source

  • Validate chunk_size in parse_form() #​244.

v0.0.23

Compare Source

  • Remove unused trust_x_headers parameter and X-File-Name fallback #​196.
  • Return processed length from QuerystringParser._internal_write #​229.
  • Cleanup metadata dunders from __init__.py #​227.

Configuration

📅 Schedule: (UTC)

  • Branch creation
    • ""
  • Automerge
    • At any time (no schedule defined)

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.


  • If you want to rebase/retry this PR, check this box

This PR was generated by Mend Renovate. View the repository job log.

@renovate renovate Bot changed the title chore(deps): update dependency python-multipart to v0.0.26 [security] chore(deps): update dependency python-multipart to v0.0.26 [security] - autoclosed Apr 18, 2026
@renovate renovate Bot closed this Apr 18, 2026
@renovate renovate Bot deleted the renovate/pypi-python-multipart-vulnerability branch April 18, 2026 14:16
@renovate renovate Bot changed the title chore(deps): update dependency python-multipart to v0.0.26 [security] - autoclosed chore(deps): update dependency python-multipart to v0.0.26 [security] Apr 21, 2026
@renovate renovate Bot reopened this Apr 21, 2026
@renovate renovate Bot force-pushed the renovate/pypi-python-multipart-vulnerability branch 2 times, most recently from 5ba39d3 to c564caa Compare April 21, 2026 18:55
@github-project-automation github-project-automation Bot moved this from Done to Dev backlog in Agent Stack Apr 21, 2026
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Labels

None yet

Projects

Status: Dev backlog

Development

Successfully merging this pull request may close these issues.

0 participants