Security Vulnerabilities
PackageKit is a a D-Bus abstraction layer that allows the user to manage packages in a secure way using a cross-distro, cross-architecture API. PackageKit between and including versions 1.0.2 and 1.3.4 is vulnerable to a time-of-check time-of-use (TOCTOU) race condition on transaction flags that allows unprivileged users to install packages as root and thus leads to a local privilege escalation. This is patched in version 1.3.5.
A local unprivileged user can install arbitrary RPM packages as root, including executing RPM scriptlets, without authentication. The vulnerability is a TOCTOU race condition on `transaction->cached_transaction_flags` combined with a silent state-machine guard that discards illegal backward transitions while leaving corrupted flags in place. Three bugs exist in `src/pk-transaction.c`:
1. Unconditional flag overwrite (line 4036): `InstallFiles()` writes caller-supplied flags to `transaction->cached_transaction_flags` without checking whether the transaction has already been authorized/started. A second call blindly overwrites the flags even while the transaction is RUNNING.
2. Silent state-transition rejection (lines 873–882): `pk_transaction_set_state()` silently discards backward state transitions (e.g. `RUNNING` → `WAITING_FOR_AUTH`) but the flag overwrite at step 1 already happened. The transaction continues running with corrupted flags.
3. Late flag read at execution time (lines 2273–2277): The scheduler's idle callback reads cached_transaction_flags at dispatch time, not at authorization time. If flags were overwritten between authorization and execution, the backend sees the attacker's flags.
CVSS Score
8.8
EPSS Score
0.002
Published
2026-04-22
A client might theoretically be able to cause a mismatch between queries sent to a backend and the received responses by sending a flood of perfectly timed queries that are routed to a TCP-only or DNS over TLS backend.
CVSS Score
3.1
EPSS Score
0.0
Published
2026-04-22
PRSD detection denial of service
CVSS Score
3.7
EPSS Score
0.0
Published
2026-04-22
A cached crafted response can cause an out-of-bounds read if custom Lua code calls getDomainListByAddress() or getAddressListByDomain() on a packet cache.
CVSS Score
4.8
EPSS Score
0.0
Published
2026-04-22
A rogue backend can send a crafted SVCB response to a Discovery of Designated Resolvers request, when requested via either the autoUpgrade (Lua) option to newServer or auto_upgrade (YAML) settings. DDR upgrade is not enabled by default.
CVSS Score
3.1
EPSS Score
0.0
Published
2026-04-22
A rogue backend can send a crafted UDP response with a query ID off by one related to the maximum configured value, triggering an out-of-bounds write leading to a denial of service.
CVSS Score
6.5
EPSS Score
0.0
Published
2026-04-22
An attacker can send a notify request that causes a new secondary domain to be added to the bind backend, but causes said backend to update its configuration to an invalid one, leading to the backend no longer able to run on the next restart, requiring manual operation to fix it.
CVSS Score
7.4
EPSS Score
0.0
Published
2026-04-22
Incomplete escaping of LDAP queries when running with 8bit-dns enabled allows users to perform queries of internal domain subtrees.
CVSS Score
5.3
EPSS Score
0.0
Published
2026-04-22
A rogue primary server may cause file descriptor exhaustion and eventually a denial of service, when a PowerDNS secondary server forwards a DNS update request to it.
CVSS Score
5.9
EPSS Score
0.0
Published
2026-04-22
An attacker can create a large number of concurrent DoQ or DoH3 connections, causing unlimited memory allocation in DNSdist and leading to a denial of service. DOQ and DoH3 are disabled by default.
CVSS Score
5.3
EPSS Score
0.0
Published
2026-04-22