In Other News: Anthropic Breach Dispute, UEFI Flaw Hits Most Servers, Cloudflare AI Data Leak

What it is

SecurityWeek's roundup of 30 October 2026 carries three items an engineer can act on: a PXE-boot buffer overflow in TianoCore EDK II (CVE-2026-97631), a cross-tenant leak in SGLang that Cloudflare fixed on Workers AI, and a bot campaign that impersonates AI crawlers to scan for secret files. The other items are brief news notes with no stated remediation.

How it works

CVE-2026-97631. The flaw is a 16-year-old buffer overflow in TianoCore EDK II, which AMI, Insyde and Phoenix use in their firmware. An attacker with local network access sends an oversized ICMP error message to a machine while it boots over the network (PXE). The result is a hung boot or, if the attacker knows the target's firmware build, code execution at the highest privilege level before defenses such as Secure Boot take effect. Anthropic and Google researchers found it.

SGLang leak. Cloudflare's GLM 5.3 deployment had a KV cache smaller than its advertised context window. An SGLang bug let requests longer than the cache read data left by earlier sessions. Between 27 August and 9 September 2026, 155 responses contained other customers' recent request data. All involved prompts longer than 681,280 tokens.

Fake AI bots. Cequence tracked one actor rotating through about 32 AI bot identities (OpenAI, Anthropic, Meta, Perplexity and others). It probes for .env files, cloud credentials and private SSH keys. It ran from a major cloud provider since at least late September 2026 and used over 300 IP addresses in one day. On one day in October it reached 48% of Cequence-protected organizations that saw any AI bot traffic.

Preconditions / Affected

• CVE-2026-97631 matters only for machines that use network boot. Exposure also requires the attacker to be on the local network.
• The SGLang leak affects SGLang operators serving long-context models. Cloudflare found no evidence of deliberate exploitation on its platform.
• The secret-file probing hits any public site that serves such files.

What to do

• Ask your firmware vendor for an update for CVE-2026-97631. The flaw became public months before the planned January disclosure, after AMI published a code fix, so vendor patches may lag. The page names no other mitigation.
• Update SGLang to version 0.5.22 or later, as Cloudflare recommends.
• Do not trust a bot's self-declared identity. Cequence found the impersonator made up more than 80% of traffic labeled as AI bot traffic at some organizations. Make sure secret files are not web-reachable.

Caveats

The page is a secondary summary citing Ars Technica and Cequence, and gives no patch versions for the firmware. It names no detection queries or indicators for the bot campaign. Anthropic's dispute with Cathedral over the scope of a bug bounty intrusion is contested on both sides, and the underlying report is paywalled.