VulnerabilityPublished 6 Nov 2024Updated 3 Nov 2025

CVE-2024-9681: curl · Comparison Using Wrong Factors

Affects curlSource GCVE Database

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Not known to be exploited · CVSS 5.9 Medium.

Data as of 30 Oct 2026, 00:29 UTC

CVSS 3.1 base score

5.9Medium

How severe the flaw is on the 0–10 CVSS scale.

Thin evidence

One scorer or none

CVSS scores by source
CISA-ADP	CVSS 3.1	5.9

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

Attack Vector: Network
Attack Complexity: High
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: High
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: High: A successful attack depends on conditions beyond the attacker's control. That is, a successful attack cannot be accomplished at will, but requires the attacker to invest in some measurable amount of effort in preparation or execution against the vulnerable component before a successful attack can be expected. For example, a successful attack may require an attacker to: gather knowledge about the environment in which the vulnerable target/component exists; prepare the target environment to improve exploit reliability; or inject themselves into the logical network path between the target and the resource requested by the victim in order to read and/or modify network communications (e.g., a man in the middle attack).
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 6 Nov 2024
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
curl curl	Affected 7.74.0 – 8.10.1 37 affected builds	Fixed in–

AI-suggested

Users should monitor the official curl advisories for updates and apply any forthcoming fixes promptly. Until a fix is available, users should be aware of this behavior when using curl with HSTS and consider manual cache management or avoiding mixed subdomain and parent domain HTTP requests that rely on HSTS enforcement.

Description

CVE-2024-9681 is a vulnerability in curl's handling of HSTS (HTTP Strict Transport Security) cache entries. The flaw causes the expiry time for a subdomain's HSTS entry to incorrectly overwrite the parent domain's cache entry, resulting in an incorrect expiry time for the parent domain. This can cause curl to either prematurely revert to HTTP or continue enforcing HTTPS longer than intended for the parent domain, potentially leading to access failures or unintended protocol enforcement.

Impact

The impact is an incorrect enforcement period of HTTPS for the parent domain due to cache expiry time bleeding from a subdomain. This can lead to curl failing to access the parent domain over HTTP when HTTPS support has ended but curl still enforces HTTPS, or conversely, reverting to HTTP earlier than intended, potentially reducing security. There is no direct confidentiality or availability impact reported, but the integrity of protocol enforcement is affected.

Summary

This vulnerability in curl affects applications that enable HSTS and use URLs with the HTTP scheme involving both a subdomain and its parent domain. When a subdomain responds with a Strict-Transport-Security header, curl's HSTS cache may incorrectly apply the subdomain's expiry time to the parent domain's cache entry. This misapplication can cause HTTP accesses to the parent domain to be upgraded to HTTPS for a period different from what the origin server specified. The issue arises only if the HSTS cache was previously populated, either manually or through prior HTTPS accesses. The bug can cause curl to fail accessing the parent domain over HTTP if HTTPS support ends at the wrongly extended expiry time or revert to HTTP earlier than intended if the expiry is shortened.

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 30 Oct 2026, 00:29 UTC

WeaknessesCWE-1025

Technical details

References

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