NGINX Plus: Use After Free
CVE-2024-24990 is a high-severity use after free vulnerability in NGINX Plus from F5, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions R31 P1, R30 P2 as the first without the flaw, so updating NGINX Plus to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.91% chance of exploitation within 30 days, higher than 60% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update NGINX Plus to R31 P1 or R30 P2, whichever matches your release line, or a later version.
- Update NGINX Open Source to 1.25.4 or a later version.
- Read the advisory on my.f5.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| F5 | NGINX Plus | R31 up to, but not including, R31 P1; R30 up to, but not including, R30 P2 | R31 P1, R30 P2 |
| F5 | NGINX Open Source | 1.25.0 up to, but not including, 1.25.4 | 1.25.4 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.5 | High | CNA (f5.com) |
| CVSS 3.1 | 7.5 | High | NVD |
Official description
When NGINX Plus or NGINX OSS are configured to use the HTTP/3 QUIC module, undisclosed requests can cause NGINX worker processes to terminate. Note: The HTTP/3 QUIC module is not enabled by default and is considered experimental. For more information, refer to Support for QUIC and HTTP/3 https://nginx.org/en/docs/quic.html . Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Use After Free
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.
How developers prevent this class of flaw
- Choose a language that provides automatic memory management.
- When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Other references
- openwall.com/lists/oss-security/2024/05/30/4Mailing List
Other vulnerabilities in NGINX Plus
- 8.1 High severity
- 8.1 High severity
- 8.1 High severity
- 8.2 High severity
- 8.1 High severity
- 8.1 High severity
Recent Use After Free vulnerabilities
- 8.1 High severity
- 7.5 High severity
- 7.8 High severity
- 9.8 Critical severity
- 7.5 High severity
- 7.0 High severity
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