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

Goal: 1000 CNY · Raised: 1336 CNY

100%
Buy Us a Coffee

CVE-2026-50285— Pomerium: Pre-Auth Memory Exhaustion via Unbounded zstd Decompression in HPKE Callback

Quick assessment

Affected
pomerium pomerium
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.

Pomerium 是一个具备身份和上下文感知能力的访问代理。在 0.32.8 之前的版本中， 中的 在处理 中 处理的 HPKE V2 值（用于 ）时，对攻击者可控的数据执行 zstd 解压缩，但缺乏输出内存限制。 在托管或无状态身份验证部署环境中，未认证的访问者可以先从 获取接收方公钥，提供与之匹配的攻击者可控的发送方公钥，并向 发送一个压缩负载。该负载会在 拒绝该发送方之前被展开，导致每次请求分配数百兆字节内存，从而耗尽代理内存，可能导致进程崩溃或性能下降，并阻止对由该部署保护的应用程序进行访问。 有状态部署不

CVSS 7.5 · High

Affected Version Matrix 1

VendorProduct Version RangeStatus
pomerium pomerium < 0.32.8 affected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-50285

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Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.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
Pomerium: Pre-Auth Memory Exhaustion via Unbounded zstd Decompression in HPKE Callback
Source: CVE Program / CVE List V5
Vulnerability Description
Pomerium is an identity and context-aware access proxy. Prior to 0.32.8, decodeQueryStringV2 in pkg/hpke/url.go performs zstd decompression of attacker-controlled data without an output-memory limit when DecryptURLValues processes HPKE V2 values for Stateless.Callback in internal/authenticateflow/stateless.go. In hosted or stateless authentication deployments, an unauthenticated attacker can obtain the receiver key from /.well-known/pomerium/hpke-public-key, provide a matching attacker-controlled sender key, and send a compressed payload to /.pomerium/callback that expands before validateSenderPublicKey rejects the sender. This can allocate hundreds of megabytes per request, exhaust proxy memory, crash or degrade the process, and block access to applications protected by the deployment. Stateful deployments are not affected because the stateful callback verifies its HMAC signature before decryption and decompression. This issue is fixed in version 0.32.8.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
CWE-1284
Source: CVE Program / CVE List V5

Affected Products

Vendor Product Affected Versions CPE Subscribe
pomerium pomerium < 0.32.8 -

II. Public POCs for CVE-2026-50285

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-50285

请登录查看更多情报信息。

Patches & Fixes for CVE-2026-50285 (1)

Vendor Advisories for CVE-2026-50285 (1)

Vendor Pages for CVE-2026-50285 (1)

IV. Related Vulnerabilities

Same product: pomerium
Same vendor: pomerium
Same weakness: CWE-1284

V. Comments for CVE-2026-50285

No comments yet

Leave a comment