Undici up to 7.29.0/8.10.1 Decompress Interceptor resource consumption

Summaryinfo

A vulnerability classified as problematic has been found in Undici up to 7.29.0/8.10.1. This impacts an unknown function of the component Decompress Interceptor. Performing a manipulation results in resource consumption. This vulnerability is identified as CVE-2026-84890. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in Undici up to 7.29.0/8.10.1. It has been classified as problematic. This affects some unknown processing of the component Decompress Interceptor. The manipulation with an unknown input leads to a resource consumption vulnerability. CWE is classifying the issue as CWE-400. The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources. This is going to have an impact on availability. The summary by CVE is:

undici's decompress interceptor decompresses response bodies according to the untrusted Content-Encoding header. While the number of content-encoding layers is capped, the total decompressed output size is unbounded and there is no configuration option to limit it. A malicious or faulty upstream can therefore return a small compressed payload, a compression bomb, that expands to hundreds of megabytes or more in client memory, an asymmetric resource consumption that can exhaust memory and crash the process. This affects undici versions from 7.15.0 up to 7.29.1 and from 8.0.0 up to 8.10.2. Users should upgrade to undici 7.29.1 or 8.10.2.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-84890 since 09/02/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1499 according to MITRE ATT&CK.

Upgrading to version 7.29.1 or 8.10.2 eliminates this vulnerability.

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Productinfo

Name

• Undici

Version

• 7.0
• 7.1
• 7.2
• 7.3
• 7.4
• 7.5
• 7.6
• 7.7
• 7.8
• 7.9
• 7.10
• 7.11
• 7.12
• 7.13
• 7.14
• 7.15
• 7.16
• 7.17
• 7.18
• 7.19
• 7.20
• 7.21
• 7.22
• 7.23
• 7.24
• 7.25
• 7.26
• 7.27
• 7.28
• 7.29.0
• 8.10.0
• 8.10.1

CPE 2.3info

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CPE 2.2info

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• 🔒
• 🔒

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Entryinfo

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