CVE-2023-33251 — When Akka HTTP before 10

When Akka HTTP before 10.5.2 accepts file uploads via the FileUploadDirectives.fileUploadAll directive, the temporary file it creates has too weak permissions: it is readable by other users on Linux or UNIX, a similar issue to CVE-2022-41946.

01What is this vulnerability?

When Akka HTTP before 10.5.2 accepts file uploads via the FileUploadDirectives.fileUploadAll directive, the temporary file it creates has too weak permissions: it is readable by other users on Linux or UNIX, a similar issue to CVE-2022-41946.

02Affected products

No structured affected-product list available — see references below for vendor advisories.

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

08Timeline

• Published: 2023-05-21T21:15:08.790
• Last modified: 2026-06-17T06:01:24.957

09References

• akka.io — https://akka.io/security/akka-http-cve-2023-05-15.html
• akka.io — https://akka.io/security/akka-http-cve-2023-05-15.html
• doc.akka.io — https://doc.akka.io/reference/security-announcements/akka-http-cve-2023-05-15.ht…