CVE-2023-28320A denial of service vulnerability exists in curl <v8.1.0 in the way libcurl provides several different backends for resolving host names,…
- 5.9MediumCVSS base score
- 2.7%Exploitation in 30 daysEPSS · top 14% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- YesPublic exploitsa reference or SSVC says so
Description
A denial of service vulnerability exists in curl <v8.1.0 in the way libcurl provides several different backends for resolving host names, selected at build time. If it is built to use the synchronous resolver, it allows name resolves to time-out slow operations using `alarm()` and `siglongjmp()`. When doing this, libcurl used a global buffer that was not mutex protected and a multi-threaded application might therefore crash or otherwise misbehave.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. CISA's SSVC rates its exploitation: a proof of concept is public.
Timeline
ID reserved
By hackerone
- 2 months later
· 2 months later
Published
- 20 months later
· 20 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADPADP (enrichment) | 3.1 | Medium5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVDNVD · Modified | 3.1 | Medium5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 2.7% · top 14% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.9.
Affected products
https://github.com/curl/curl
- affected Fixed in 8.1.0
References
References9
- https://hackerone.com/reports/1929597 (opens in a new tab)x_transferred
- https://security.netapp.com/advisory/ntap-20230609-0009/ (opens in a new tab)x_transferred
- https://support.apple.com/kb/HT213843 (opens in a new tab)x_transferred
- https://support.apple.com/kb/HT213844 (opens in a new tab)x_transferred
- https://support.apple.com/kb/HT213845 (opens in a new tab)x_transferred
- 20230725 APPLE-SA-2023-07-24-6 macOS Big Sur 11.7.9 (opens in a new tab)mailing-listx_transferred
- 20230725 APPLE-SA-2023-07-24-5 macOS Monterey 12.6.8 (opens in a new tab)mailing-listx_transferred
- 20230725 APPLE-SA-2023-07-24-4 macOS Ventura 13.5 (opens in a new tab)mailing-listx_transferred
- GLSA-202310-12 (opens in a new tab)vendor-advisoryx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2023-32027 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2023-28320)Record last updated .