Quick answers
- Is CVE-2026-53671 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-53671 being exploited in the wild.
- How severe is CVE-2026-53671?
- Informational severity, with a CVSS score of 0, published 2 September 2026.
- Which products and versions are affected?
- vBPF Prevail before 0.2.4.
- Is there a fix for CVE-2026-53671?
- A patch was published on 2026-06-01. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-53671 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-53671?
- Check whether you run vBPF Prevail at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
The vulnerability is a logic error in PREVAIL's abstract transformer (src/crab/ebpf_transformer.cpp). The do_mem_store function only models T_STACK stores and ignores writes through T_CTX-typed base registers, treating them as silent no-ops. Additionally, the T_CTX case in the ValidAccess checker never inspects AccessType::write, only the default read operation. An attacker can craft an eBPF program that writes to a context field like ctx->data (which should be read-only), then reload that field as a typed packet pointer, and dereference an attacker-controlled address. PREVAIL's soundness check will pass the program despite the unsafe operation. The vulnerability was patched in version 0.2.4 by adding logic to reject writes that overlap read-only pointer slots while allowing writes to scalar context fields.
Affected products
- vbpf PREVAIL before 0.2.4
Timeline
- 2026-09-02: disclosed
- 2026-06-01: patched