CVE-2023-45675 | 0 byte write heap buffer overflow in start_decoder in stb_vorbis

stb_vorbis is a single file MIT licensed library for processing ogg vorbis files. A crafted file may trigger out of bounds write in `f->vendor[len] = (char)'\0';`. The root cause is that if the len read in `start_decoder` is `-1` and `len + 1` becomes 0 when passed to `setup_malloc`. The `setup_malloc` behaves differently when `f->alloc.alloc_buffer` is pre-allocated. Instead of returning `NULL` as in `malloc` case it shifts the pre-allocated buffer by zero and returns the currently available memory block. This issue may lead to code execution.

Published: 2023-10-21 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-45675 is rated Moderate Risk (44.3/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.76%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2023-45675

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.09% 0.76% +0.67%
2 2025-11-21 0.30% 0.09% -0.21%
3 2025-11-18 — 0.30% —

Full EPSS history (9 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-45675

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 3.9 2.5 [email protected]
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 5.9 [email protected]

Weakness enumeration for CVE-2023-45675

OS Trackers for CVE-2023-45675

vendor priority summary link
alpine high CVE-2023-45675: 1 source package rows (stb); 6 state rows across 6 repos (3.19-community, 3.20-community, 3.21-community, 3.22-community, 3.23-community, edge-community); fixed 6, open 0. https://security.alpinelinux.org/vuln/CVE-2023-45675
debian not yet assigned CVE-2023-45675 not yet assigned priority: Debian including 1 source packages (libstb), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 5. https://security-tracker.debian.org/tracker/CVE-2023-45675
ubuntu medium CVE-2023-45675 medium priority: Ubuntu including 1 source packages (libstb), 12 status rows across 12 suites (bionic, focal, jammy, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): ignored 7, needs-triage 5. https://ubuntu.com/security/CVE-2023-45675

Affected software / configurations for CVE-2023-45675

Vendor Product Version Raw CPE
nothings stb_vorbis.c 1.22 cpe:2.3:a:nothings:stb_vorbis.c:1.22:*:*:*:*:*:*:*

References for CVE-2023-45675

cvelogic Threat Intelligence