Critical severity · published Oct 20, 2023
CVE-2023-45666
Possible double-free or memory leak in stbi__load_gif_main in stb_image
9.8
CVSS
1.1%
EPSS
No
On KEV
Description
stb_image is a single file MIT licensed library for processing images. It may look like `stbi__load_gif_main` doesn’t give guarantees about the content of output value `*delays` upon failure. Although it sets `*delays` to zero at the beginning, it doesn’t do it in case the image is not recognized as GIF and a call to `stbi__load_gif_main_outofmem` only frees possibly allocated memory in `*delays` without resetting it to zero. Thus it would be fair to say the caller of `stbi__load_gif_main` is responsible to free the allocated memory in `*delays` only if `stbi__load_gif_main` returns a non null value. However at the same time the function may return null value, but fail to free the memory in `*delays` if internally `stbi__convert_format` is called and fails. Thus the issue may lead to a memory leak if the caller chooses to free `delays` only when `stbi__load_gif_main` didn’t fail or to a double-free if the `delays` is always freed
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.1% · higher than 65% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ST
stb · nothings
<= 2.28 · source: vendor
SI
Stb Image.h · Nothings
2.28 · source: NVD
SI
Stb Image · Nothings
through 2.28 · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-45666
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-45666
Third Party Advisory
https://github.com/nothings/stb/blob/5736b15f7ea0ffb08dd38af21067c314d6a3aae9/stb_image.h#L6957
Third Party Advisory
https://github.com/nothings/stb/blob/5736b15f7ea0ffb08dd38af21067c314d6a3aae9/stb_image.h#L6962-L7045
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/NMXKOKPP4BKTNUTF5KSRDQAWOUILQZNO/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/QVABVF4GEM6BYD5L4L64RCRSXUHY6LGN/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UVQ7ONFH5GWLMXYEAJG32A3EUKUCEVCR/
Third Party Advisory
https://securitylab.github.com/advisories/GHSL-2023-145_GHSL-2023-151_stb_image_h/
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