CVE-2023-45666: stb_image is a single file MIT licensed library for processing images

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HIGH 7.3REMOTEDOWNGRADE

CVE-2023-45666 is a high-severity flaw (CVSS 7.3) affecting stb image.h. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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 fa

Why this priority

High severity
Remotely exploitable, no login, no user action

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	7.3 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	1.1% (top 35%)
CISA exploited list	No
Weakness	CWE-415
Published	2023-10-21
Last modified	2026-06-17

Publisher (CNA): GitHub, Inc. · Vendor: nothings

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2023-10-21 00:15 UTCPublished CVE record published
2026-06-17 06:29 UTCUpdated Record last modified

nothings stb image.h DOWNGRADE

Affected: 2.28

Fixed in: no fixed release known

Safe to downgrade to: a release before 2.28

1. Check installed version

apt-cache policy stb-image.h || rpm -q stb-image.h || stb-image.h --version

2. No fixed release: DOWNGRADE to a release before 2.28 (Debian / Ubuntu)

apt-cache madison stb-image.h sudo apt install stb-image.h=<VERSION_BEFORE_2.28> sudo apt-mark hold stb-image.h

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list stb-image.h sudo dnf downgrade stb-image.h-<VERSION_BEFORE_2.28> sudo dnf versionlock add stb-image.h

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2023-45666?

stb image.h: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2023-45666 being exploited?

CVE-2023-45666 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2023-45666 affect?

CVE-2023-45666 affects stb image.h. Severity is high (CVSS 7.3). 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 begin

How urgent is CVE-2023-45666?

Priority 47/100. High severity; Remotely exploitable, no login, no user action

Related CVEs

CVE-2025-3409 MEDIUM 6.3 UPGRADE A vulnerability classified as critical has been found in Nothings stb up to f056911
CVE-2025-3408 MEDIUM 6.3 UPGRADE A vulnerability was found in Nothings stb up to f056911
CVE-2025-3407 MEDIUM 6.3 UPGRADE A vulnerability was found in Nothings stb up to f056911
CVE-2025-3406 MEDIUM 4.3 UPGRADE A vulnerability was found in Nothings stb up to f056911
CVE-2023-45667 MEDIUM 5.3 DOWNGRADE stb_image is a single file MIT licensed library for processing images. If `stbi__load_gif_main` in `stbi_load

References

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