CVE-2024-9681: HSTS subdomain overwrites parent cache entry
Affected: curl · Exploitation: possible (1 to 10%)
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Higher than 80% of scored CVEs
DescriptionCVE.org
When curl is asked to use HSTS, the expiry time for a subdomain might overwrite a parent domain's cache entry, making it end sooner or later than otherwise intended. This affects curl using applications that enable HSTS and use URLs with the insecure `HTTP://` scheme and perform transfers with hosts like `x.example.com` as well as `example.com` where the first host is a subdomain of the second host. (The HSTS cache either needs to have been populated manually or there needs to have been previous HTTPS accesses done as the cache needs to have entries for the domains involved to trigger this problem.) When `x.example.com` responds with `Strict-Transport-Security:` headers, this bug can make the subdomain's expiry timeout *bleed over* and get set for the parent domain `example.com` in curl's HSTS cache. The result of a triggered bug is that HTTP accesses to `example.com` get converted to HTTPS for a different period of time than what was asked for by the origin server. If `example.com` for example stops supporting HTTPS at its expiry time, curl might then fail to access `http://example.com` until the (wrongly set) timeout expires. This bug can also expire the parent's entry *earlier*, thus making curl inadvertently switch back to insecure HTTP earlier than otherwise intended.
Affected products1
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- curl · curlfrom 8.10.1 up to and including 8.10.1; from 8.10.0 up to and including 8.10.0; from 8.9.1 up to and including 8.9.1; from 8.9.0 up to and including 8.9.0; from 8.8.0 up to and including 8.8.0; from 8.7.1 up to and including 8.7.1 and 31 more
On the Atlas
Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.
- Exploitation
- Possible (1 to 10%). EPSS between 1% and 10%.
- CISA KEV
- Not listed
- Public check
- No public nuclei template
- Vendor
- curl
- Published
- November 2024
- Bounty reports
- 4 disclosed on HackerOne
Disclosed bug bounty reports about CVE-2024-9681
The reports on HackerOne that name this CVE, with HackerOne's own outcome. Titles and metadata only.
- CVE-2024-9681: HSTS subdomain overwrites parent cache entrycurl · 2024 · low severityValid
- One Strict-Transport-Security response header empties the victim's entire HSTS store, silently,curl · 2026 · medium severityN/A
- 14: HSTS cache import silently drops a longer-lived child beneath an includeSubDomains parentcurl · 2026Duplicate
- CVE-2026-87862: HSTS cache import drops longer-lived childcurl · 2026Valid
CoverageNo articles yet
No CyberSIXT article names CVE-2024-9681 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.
References
- NVD entrynvd.nist.gov
- CVE recordcve.org
- Weakness CWE-1025cwe.mitre.org
- curl.se/docs/CVE-2024-9681.jsoncurl.se
- curl.se/docs/CVE-2024-9681.htmlcurl.se
- hackerone.com/reports/2764830hackerone.com
- openwall.com/lists/oss-security/2024/11/06/2openwall.com
- security.netapp.com/advisory/ntap-20241213-0006security.netapp.com
- seclists.org/fulldisclosure/2025/Apr/13seclists.org
- seclists.org/fulldisclosure/2025/Apr/10seclists.org
- seclists.org/fulldisclosure/2025/Apr/9seclists.org
- seclists.org/fulldisclosure/2025/Apr/8seclists.org
- seclists.org/fulldisclosure/2025/Apr/5seclists.org
- seclists.org/fulldisclosure/2025/Apr/4seclists.org
- seclists.org/fulldisclosure/2025/Apr/12seclists.org
1 more reference is in the CVE record.