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USN-8736-1: Perl vulnerabilities

Ubuntu issued USN-8736-1 fixing two Perl regex flaws that could cause denial of service, code execution, or security-restriction bypass.

Ubuntu released a security notice addressing two Perl vulnerabilities in regular expression handling. CVE-2026-15534 involves mishandling of large inputs during regex matching, enabling out-of-bounds heap reads or writes that could lead to denial of service or arbitrary code execution. CVE-2026-19487 involves incorrect matching for regexes with alternative branches, allowing security restrictions to be bypassed. Users are advised to apply the updated packages.

ASCII smuggling crosses over from AI prompt injection to phishing evasion

Microsoft details high-volume phishing campaign using ASCII smuggling (Unicode tag chars) for filter evasion, peaking at 2.3M messages.

Microsoft researchers observed a high-volume finance-themed phishing campaign using invisible Unicode tag characters (U+E0000–U+E007F), a technique known from AI prompt injection research as ASCII smuggling, to split lure words like 'funding' and evade email filters. Telemetry from Microsoft Defender for Office 365 showed signature hits jump from roughly 21,000 messages on February 8, 2026 to more than 1.3 million on February 9, peaking above 2.3 million on February 11, with elevated weekday activity lasting approximately three months. The discovery emerged from prompt injection protection research, showing AI-era evasion techniques crossing into traditional phishing. Most messages were flagged by layered Defender protections rather than a single Unicode-specific signal.

Microsoft Security Blog · 12d agoPhishing & fraud in the wild

USN-8563-5: nginx vulnerability

Ubuntu ships improved nginx fix for CVE-2026-42533 after earlier patch regression; flaw allows remote crash and possible code execution.

USN-8563-5 provides a better fix for CVE-2026-42533 after the original fix from USN-8563-1 was backed out in USN-8563-2 because it caused a regression. The flaw stems from nginx incorrectly handling certain map directives using regex matching and capture variables, allowing a remote attacker to crash nginx, causing denial of service, or possibly execute arbitrary code. The original advisory also described a use-after-free in the ngx_http_ssi_module when configured with Server-Side Includes, proxy_pass, and proxy buffering.

ASCII smuggling isn't just an AI security risk

Microsoft tracked a phishing campaign peaking at 2.37 million daily messages that hid financial-lure keywords with invisible Unicode tag characters to evade filters.

Microsoft researchers uncovered a large phishing campaign that inserted invisible Unicode tag characters (e.g., U+E0020) inside common financial keywords like 'funding', splitting words so keyword, signature, and regex matches fail. The campaign peaked at more than 2.37 million messages in late February 2026, ran from about 150 finance-themed sender domains on a strict weekday-only schedule, and gradually declined to under 20% of peak weekday volume by late March, with residual spikes through mid-June. The technique repurposes ASCII smuggling, normally used for indirect prompt injection against AI assistants, for traditional email phishing evasion. Microsoft advises defenders to strip or fold invisible Unicode code points before content matching and to watch for bulk weekday spikes from churning finance-themed domains.

The Register · Security · 11d agoPhishing & fraud in the wild1

Gaming the system: how a Chinese-speaking actor turned Brazilian government sites into an SEO weapon

Check Point identifies Chinese-speaking group Gambling Goblin hijacking Brazilian government domains via malicious Apache modules for SEO-manipulated gambling phishing.

Check Point Research tracks a sustained campaign since mid-2025 against Brazilian government and educational organizations by Gambling Goblin, a Chinese-speaking cybercrime cluster linked to Earth Berberoka. Attackers compile and install malicious Apache modules that silently reverse-proxy visitors to phishing pages impersonating Google Play, Microsoft Store, and Amazon, chaining compromised high-reputation domains to inflate search rankings. The group deploys a heavily obfuscated Linux toolkit including DownPro, AlphaAgent, oRAT, a 3snake-based credential stealer, and SSH brute-forcers, with parallel phishing networks localized for Vietnamese, Spanish, and English victims.

Check Point Research · 13d agoThreat actor