What happened

CISA added CVE-2025-31277 to its Known Exploited Vulnerabilities (KEV) catalog on 2026-03-20, asserting active exploitation in the wild CISA KEV. The catalog entry designates the due date for remediation as 2026-04-03 and instructs organizations to apply vendor mitigations or discontinue use if mitigations are unavailable CISA KEV. The vulnerability is tracked as affecting Apple “Multiple Products,” with Apple platforms explicitly including Safari, iOS, iPadOS, macOS, watchOS, tvOS, and visionOS, and is described as a buffer overflow triggered by processing maliciously crafted web content leading to memory corruption NVD CVE-2025-31277.

The CVE record is also published at MITRE, confirming the identifier and linkage to Apple’s multi-product scope MITRE CVE-2025-31277. Classification maps to a memory safety error: improper restriction of operations within the bounds of a memory buffer (CWE‑119) NVD CVE-2025-31277.

Why it matters

When a single bug spans Apple’s core consumer and enterprise endpoints — Safari, iOS, iPadOS, macOS, watchOS, tvOS, and visionOS — it becomes ubiquitously reachable via routine web browsing or embedded web views, because exploitation is described as processing “maliciously crafted web content” NVD CVE-2025-31277. CISA’s decision to list CVE-2025-31277 in KEV means exploitation is not hypothetical; federal civilian agencies are mandated to remediate on a fixed timeline due to confirmed abuse in the wild CISA KEV. For everyone else, the KEV flag is the industry’s strongest signal to prioritize patching over standard backlog work because the threat is operational, not academic CISA KEV.

Memory corruption bugs are volatile in their outcomes — crashes, data corruption, or potential code execution — but the official description here stays at “memory corruption,” so defenders should plan for worst-case while sticking to vendor guidance NVD CVE-2025-31277. The CWE-119 mapping reinforces that this is a class of memory-safety defect repeatedly leveraged through malformed inputs, in this case untrusted web content NVD CVE-2025-31277.

Technical detail

Per the CVE entry, this is a buffer overflow in Apple Multiple Products where maliciously crafted web content may trigger memory corruption during processing NVD CVE-2025-31277. The weakness taxonomy aligns with CWE‑119 (Improper Restriction of Operations within the Bounds of a Memory Buffer), a broad category encompassing read/write past buffer boundaries NVD CVE-2025-31277. CISA’s inclusion in KEV confirms observed exploitation, with remediation deadlines applied for government networks under Binding Operational Directive policy CISA KEV.

Public records at the time of writing do not enumerate version ranges, exploit chain details, or specific components beyond the multi-product scope and the web-content trigger, and the authoritative CVE object remains the reference of record for subsequent updates MITRE CVE-2025-31277. As NVD analysis matures, severity and impact metrics may be updated; defenders should track the NVD entry for changes to scoring or references NVD CVE-2025-31277.

Defense

Do the simple, urgent thing first: apply vendor mitigations or discontinue use if you cannot mitigate by policy deadline — that’s the explicit instruction tied to KEV inclusion CISA KEV. Agencies governed by BOD timelines must complete remediation by the listed due date (2026-04-03 for this entry) and document exception handling where applicable CISA KEV. For enterprises, fold this into emergency change windows for Apple fleets that process untrusted web content across Safari or embedded browsers, since the trigger condition is web-content processing NVD CVE-2025-31277.

Operationally:

• Inventory and patch Apple platforms flagged in the advisory scope — Safari, iOS, iPadOS, macOS, watchOS, tvOS, and visionOS — prioritizing high-exposure endpoints that routinely browse external sites NVD CVE-2025-31277.
• Track remediation against the KEV due date and enforce exception timeboxes consistent with mandated guidance CISA KEV.
• Monitor vendor advisories linked from the CVE/NVD record for updated mitigations or post-patch hardening notes as they publish NVD CVE-2025-31277.

Because the exploit vector is untrusted web content, traditional network signatures will lag, and endpoint exploit prevention should be assumed imperfect until patched; KEV status indicates adversaries already have working techniques in the field CISA KEV. Keep detection focused on patch compliance and rapid containment rather than speculative IOC chasing for a memory-corruption class issue NVD CVE-2025-31277.

Lyrie Verdict

CVE-2025-31277 is live-fire: CISA’s KEV designation means exploitation is happening now, on endpoints that render web content across Apple ecosystems CISA KEV. Lyrie treats KEV additions as machine-speed policy events — we auto-ingest CVE metadata from NVD/KEV and drive enforcement of remediation SLAs tied to the KEV due date for every in-scope asset NVD CVE-2025-31277. For this class of memory-corruption web-content bugs (CWE‑119), prevention is patching; Lyrie’s autonomous workflows prioritize affected Apple platforms and block risky exposure paths until assets are remediated, aligning with the “apply mitigations or discontinue use” directive CISA KEV. When rogue automation iterates exploit content faster than humans can triage, KEV-aware, CVE-grounded control at machine speed is the difference between containment and compromise MITRE CVE-2025-31277.