Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%

Buy Us a Coffee

CVE-2026-125209— FFmpeg before 8.1.3 and 9.x before 9.0.2 Heap Buffer Overflow via dvdsubenc.c

Quick assessment

Affected

FFmpeg FFmpeg

Exploitation

No confirmed in-the-wild exploitation; assess based on exposure

Recommended action

Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

FFmpeg 8.1.3 之前版本以及 9.x 系列中 9.0.2 之前的版本，其 DVD 字幕编码器存在堆缓冲区溢出漏洞。该漏洞源于编码器对奇数宽度矩形的游程编码（RLE）输出尺寸估算不足。攻击者可构造包含特制位图字幕的文件，当这些文件被转码至 dvdsub 编码器时，会导致数据写入超出输出缓冲区范围，进而破坏堆内存。

CVSS 7.8 · High Updated Nov 10, 2026

Possible ATT&CK Techniques 2 AI

T1068 · Exploitation for Privilege Escalation T1190 · Exploit Public-Facing Application

Affected Version Matrix 2

Vendor	Product	Version Range	Status
FFmpeg	FFmpeg	`< 8.1.3`	affected
		`9.0< 9.0.2`	affected

Get alerts for future matching vulnerabilities Log in to subscribe

Vulnerability Information

Have questions about the vulnerability? See if Shenlong's analysis helps!

View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title

FFmpeg before 8.1.3 and 9.x before 9.0.2 Heap Buffer Overflow via dvdsubenc.c

Source: CVE Program / CVE List V5

Vulnerability Description

FFmpeg before 8.1.3 and 9.x before 9.0.2 contains a heap buffer overflow vulnerability in the DVD subtitle encoder that underestimates RLE output size for odd-width rectangles. Attackers can supply files with crafted bitmap subtitles that, when transcoded to the dvdsub encoder, write past the output buffer and corrupt heap memory.

Source: CVE Program / CVE List V5

CVSS Information

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Source: CVE Program / CVE List V5

Vulnerability Type

缓冲区大小计算不正确

Source: CVE Program / CVE List V5

Affected Products

Vendor	Product	Affected Versions	CPE	Subscribe
FFmpeg	FFmpeg	0 ~ 8.1.3	-

II. Public POCs for CVE-2026-125209

#	POC Description	Source Link	Shenlong Link

AI-Generated POC Premium

No public POC found.

III. Intelligence Information for CVE-2026-125209

请登录查看更多情报信息。

Other References for CVE-2026-125209 (4)

https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24486 issue-tracking
https://github.com/FFmpeg/FFmpeg/blob/n9.0.1/libavcodec/dvdsubenc.c#L344 technical-description
https://github.com/FFmpeg/FFmpeg/commit/8702f12c9daa199cc4d7c17164b13c3cdcdc2436 patch
https://www.vulncheck.com/advisories/ffmpeg-before-8.1.3-and-9-x-before-9.0.2-heap-buffer-overflow-via-dvdsubenc-c third-party-advisory

https://www.cve.org/CVERecord?id=CVE-2026-125209

Same Patch Batch · FFmpeg · 2026-11-09 · 121 CVEs total

CVE-2026-125233	7.8 HIGH	FFmpeg through 9.0.2 Heap Buffer Overflow via DVB Subtitle Encoder
CVE-2026-125250	7.8 HIGH	FFmpeg through 9.0.2 GIF Encoder Heap Buffer Overflow via shrunk_buf Remap
CVE-2026-125267	7.8 HIGH	FFmpeg before 8.1.3 and 9.x before 9.0.2 Heap Out-of-Bounds Write via APAC Decoder
CVE-2026-125262	7.8 HIGH	FFmpeg through 9.0.2 Heap Buffer Overflow via LCEVC Enhancement Decoding
CVE-2026-125203	7.8 HIGH	FFmpeg before 8.1.3 and 9.x before 9.0.2 Heap Buffer Overflow in Cook Multichannel Decoder
CVE-2026-125259	7.8 HIGH	FFmpeg through 9.0.2 Heap Buffer Overflow via ProRes prores_ks Encoder
CVE-2026-125229	7.8 HIGH	FFmpeg through 9.0.2 Out-of-Bounds Memory Access in Huffyuv/FFVHUFF Median Predictor
CVE-2026-125244	7.8 HIGH	FFmpeg before 8.1.3 and 9.x before 9.0.2 VVC Decoder Out-of-Bounds Write via sh_entry_poin
CVE-2026-125212	7.0 HIGH	FFmpeg through 9.0.2 Heap Buffer Overflow via VideoToolbox Encoder
CVE-2026-125211	7.0 HIGH	FFmpeg through 9.0.2 Heap Corruption via libaribcaption ASS Error Cleanup
CVE-2026-125219	7.0 HIGH	FFmpeg through 9.0.2 Heap Buffer Overflow via HEVC VDPAU Tile Arrays
CVE-2026-125218	7.0 HIGH	FFmpeg through 9.0.2 APNG Encoder Heap Buffer Overflow via encode_apng()
CVE-2026-125235	7.0 HIGH	FFmpeg through 9.0.2 Heap Overflow via QSV Encoder submit_frame()
CVE-2026-125257	7.0 HIGH	FFmpeg through 9.0.2 Heap Overflow via Nellymoser Encoder Trellis Search
CVE-2026-125248	7.0 HIGH	FFmpeg 9.0 through 9.0.2 Integer Overflow via FFV1 Vulkan Encoder Remap Buffer
CVE-2026-125213	7.0 HIGH	FFmpeg through 9.0.2 Heap Buffer Overflow via PSD Decoder RLE Path
CVE-2026-125241	7.0 HIGH	FFmpeg through 9.0.2 Heap Buffer Overflow via FLIC Decoder check_pixel_ptr
CVE-2026-125202	7.0 HIGH	FFmpeg through 9.0.2 Heap Buffer Overflow via HEVC VAAPI Tile Arrays
CVE-2026-125239	7.0 HIGH	FFmpeg through 9.0.2 Heap Buffer Overflow via HEVC DXVA Tile Parameters
CVE-2026-125196	7.0 HIGH	FFmpeg through 9.0.2 Heap Buffer Overflow via liboapv APV Encoder Wrapper

Showing top 20 of 121 CVEs. View all on vendor page → →

IV. Related Vulnerabilities

Same product: FFmpeg

Same vendor: FFmpeg

Same weakness: CWE-131