CVE-2026-40339 | libgphoto2 has OOB read in ptp_unpack_Sony_DPD() FormFlag parsing in ptp-pack.c

libgphoto2 is a camera access and control library. Versions up to and including 2.5.33 have an out-of-bounds read in `ptp_unpack_Sony_DPD()` in `camlibs/ptp2/ptp-pack.c` (line 842). The function reads the FormFlag byte via `dtoh8o(data, *poffset)` without a prior bounds check. The standard `ptp_unpack_DPD()` at lines 686–687 correctly validates `*offset + sizeof(uint8_t) > dpdlen` before this same read, but the Sony variant omits this check entirely. Commit 09f8a940b1e418b5693f5c11e3016a1ad2cea62d fixes the issue.

Published: 2026-04-18 Last update: 2026-04-20 Assigner: [email protected] Source: [email protected]
NVD Status：Deferred，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-40339 is rated Low Risk (21/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.01%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

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-2026-40339

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 2026-04-18 — 0.01% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-40339

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.2 3.1 MEDIUM
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:L Click to expand
Attack vector (AV:P)
Hands-on access—USB, keyboard, opening the case—not something you do purely over the wire.
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:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 0.9 4.2 [email protected]

Weakness enumeration for CVE-2026-40339

OS Trackers for CVE-2026-40339

vendor priority summary link
debian not yet assigned CVE-2026-40339 not yet assigned priority: Debian including 1 source packages (libgphoto2), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 5. https://security-tracker.debian.org/tracker/CVE-2026-40339
suse medium — https://www.suse.com/security/cve/CVE-2026-40339/
ubuntu medium CVE-2026-40339 medium priority: Ubuntu including 1 source packages (libgphoto2), 9 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): needs-triage 9. https://ubuntu.com/security/CVE-2026-40339

Affected software / configurations for CVE-2026-40339

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-40339

cvelogic Threat Intelligence