VDB-131583 · CVE-2019-9721 · BID 108034

FFmpeg 4.1 Subtitle Decoder htmlsubtitles.c handle_open_brace Video File out-of-bounds

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.4$0-$5k0.00

Summaryinfo

A vulnerability marked as problematic has been reported in FFmpeg 4.1. Affected by this issue is the function handle_open_brace of the file libavcodec/htmlsubtitles.c of the component Subtitle Decoder. Performing a manipulation as part of Video File results in out-of-bounds. This vulnerability was named CVE-2019-9721. The attack may be initiated remotely. There is no available exploit.

Detailsinfo

A vulnerability, which was classified as problematic, was found in FFmpeg 4.1 (Multimedia Processing Software). This affects the function handle_open_brace of the file libavcodec/htmlsubtitles.c of the component Subtitle Decoder. The manipulation as part of a Video File leads to a out-of-bounds vulnerability. CWE is classifying the issue as CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. This is going to have an impact on availability. The summary by CVE is:

A denial of service in the subtitle decoder in FFmpeg 4.1 allows attackers to hog the CPU via a crafted video file in Matroska format, because handle_open_brace in libavcodec/htmlsubtitles.c has a complex format argument to sscanf.

The bug was discovered 02/06/2019. The weakness was presented 03/12/2019 (Website). It is possible to read the advisory at securityfocus.com. This vulnerability is uniquely identified as CVE-2019-9721 since 03/12/2019. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability was handled as a non-public zero-day exploit for at least 34 days. During that time the estimated underground price was around $0-$5k. The commercial vulnerability scanner Qualys is able to test this issue with plugin 197450 (Ubuntu Security Notification for Ffmpeg Vulnerabilities (USN-3967-1)).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at SecurityFocus (BID 108034†). See VDB-123171, VDB-131582, VDB-133857 and VDB-133858 for similar entries. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.4

VulDB Base Score: 4.3
VulDB Temp Score: 4.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Patch: git.ffmpeg.org

Timelineinfo

02/06/2019 🔍
03/12/2019 +34 days 🔍
03/12/2019 +0 days 🔍
03/12/2019 +0 days 🔍
04/18/2019 +37 days 🔍
07/31/2023 +1565 days 🔍

Sourcesinfo

Product: ffmpeg.org

Advisory: 894995c41e0795c7a44f81adc4838dedc3932e65⛔
Status: Confirmed

CVE: CVE-2019-9721 (🔍)
GCVE (CVE): GCVE-0-2019-9721
GCVE (VulDB): GCVE-100-131583
SecurityFocus: 108034 - FFmpeg CVE-2019-11338 Denial of Service Vulnerability

See also: 🔍

Entryinfo

Created: 03/12/2019 15:44
Updated: 07/31/2023 15:04
Changes: 03/12/2019 15:44 (62), 05/29/2020 14:46 (4), 07/31/2023 14:59 (4), 07/31/2023 15:04 (1)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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