CVE-2026-76505
A vulnerability in the IPv4 packet processing functionality of Cisco IOS XR Software that affects…
- Risk score
- 65/100
- CVSS
- 7.5 v3.1
- Exploit chance (30 days)
- 0.3%
- Published
- 21 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- A vulnerability in Cisco IOS XR Software's IPv4 packet processing functionality allows an unauthenticated, remote attacker to cause network processor errors, resulting in a line card reset or shutdown and a denial of service (DoS) condition.
- Affected
- {'products': ['Cisco ASR 9000 and 9900 Series Aggregation Services Routers', 'Cisco ASR 9902 and 9903 Compact High-Performance Routers'], 'packages': [], 'versions': []}
- Fix
- Check the linked advisory for a fix, as none is specified.
- Exploitation
- No known exploitation
Why it is Amber
- CVSS 7.5 high
- Remotely exploitable without logging in
- On your watchlist: cisco
References
Original description
A vulnerability in the IPv4 packet processing functionality of Cisco IOS XR Software that affects Cisco ASR 9000 and 9900 Series Aggregation Services Routers as well as Cisco ASR 9902 and 9903 Compact High-Performance Routers could allow an unauthenticated, remote attacker to cause network processor (NP) errors, resulting in a line card reset or shutdown and a denial of service (DoS) condition. This vulnerability is due to the incorrect handling of crafted IPv4 packets that are received on an affected line card interface and processed as for-us traffic. The issue can result in an NP reset, causing traffic loss on the affected line card while it recovers. Under repeated reset conditions, the network processor may enter a persistent shutdown state, in which case an explicit line card reload may be required to restore traffic. The vulnerability is within the IPv4 packet-processing path. Transit IPv4 traffic does not trigger this issue and IPv6 traffic cannot trigger it.
Last activity 21 Oct 2026. Patch Forecast updates every hour.