CVE-2026-4878 · cross-distro fix matrix

CVE-2026-4878: A flaw was found in libcap. A local unprivileged user can exploit a Time-of-check-to-time-of-use (TOCTOU) race condition in the `cap_set_file()` function. This allows an attacker with write access to a parent directory to redirect file capability updates to an attacker-controlled file. By doing so,

Affects 5 Linux releases across 5 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2026-4878 has a known fix. Run the listed command on that distro to remediate.

Debian bookworm

Source: Debian Security Tracker

libcap2→ fixed in1:2.66-4+deb12u3urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libcap2
```

Debian trixie

Source: Debian Security Tracker

libcap2→ fixed in1:2.75-10+deb13u1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libcap2
```

Alpine v3.20

Source: Alpine secdb

libcap→ fixed in2.78-r0
```
apk update && apk add --upgrade libcap
```

Alpine v3.21

Source: Alpine secdb

libcap→ fixed in2.78-r0
```
apk update && apk add --upgrade libcap
```

Alpine edge

Source: Alpine secdb

libcap→ fixed in2.78-r0
```
apk update && apk add --upgrade libcap
```

Are YOU affected by CVE-2026-4878?

5-second check on your actual server. Reads /etc/os-release, uname -r, and the distro's package manager; matches against this same cross-source index live.

curl https://mindsparkstack.com/scan.sh | bash

Form-based quickscan View on NVD

Continuous monitoring beats manual checking

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