CVE-2020-8927
Buffer overflow in Brotli library
No known exploitation. EPSS puts it in the 88th percentile. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
What it is
From the CVE record
A buffer overflow exists in the Brotli library versions prior to 1.0.8 where an attacker controlling the input length of a "one-shot" decompression request to a script can trigger a crash, which happens when copying over chunks of data larger than 2 GiB. It is recommended to update your Brotli library to 1.0.8 or later. If one cannot update, we recommend to use the "streaming" API as opposed to the "one-shot" API, and impose chunk size limits.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
3.2% chance of exploitation activity in the next 30 days, which ranks it in the 88th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
6 events over 2109 days, from the signal feeds we watch.
- OpenVAS check added
- Patch availablerecord updated
- Publishedweakness classified, att&ck mapped
Affected products
- Microsoft.NETCore.App.Runtime.linux-armOSS Libraries
- Microsoft.NETCore.App.Runtime.linux-arm64OSS Libraries
- Microsoft.NETCore.App.Runtime.linux-musl-arm64OSS Libraries
- Microsoft.NETCore.App.Runtime.linux-x64OSS Libraries
- Microsoft.NETCore.App.Runtime.osx-x64OSS Libraries
- Microsoft.NETCore.App.Runtime.win-armOSS Libraries
- Microsoft.NETCore.App.Runtime.win-arm64OSS Libraries
- Microsoft.NETCore.App.Runtime.win-x64OSS Libraries
And 121 more affected products. See all after sign-in
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Scored 5.3 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality NoneNo confidentiality impact
- Integrity LowData modification is possible but limited in scope or consequence
- Availability NoneNo availability impact
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
- Initial AccessT1190Exploit Public-Facing Applicationhigh confidence
- Privilege EscalationT1068Exploitation for Privilege Escalationhigh confidence
Sources
References in the record
- lists.opensuse.org/opensuse-security-announce/2020-09/msg00108.html
- github.com/google/brotli/releases/tag/v1.0.9
- lists.debian.org/debian-lts-announce/2020/12/msg00003.html
And 45 more references. See all after sign-in
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