In PHP versions 8.1.* before 8.1.31, 8.2.* before 8.2.26, 8.3.* before 8.3.14, due to an error in convert.quoted-printable-decode filter certain data can lead to buffer overread by one byte, which can in certain circumstances lead to crashes or disclose content of other memory areas.
Weakness
A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().
Affected Software
| Name |
Vendor |
Start Version |
End Version |
| Php |
Php |
8.1.0 (including) |
8.1.31 (excluding) |
| Php |
Php |
8.2.0 (including) |
8.2.26 (excluding) |
| Php |
Php |
8.3.0 (including) |
8.3.14 (excluding) |
| Php5 |
Ubuntu |
trusty/esm |
* |
| Php7.0 |
Ubuntu |
esm-infra/xenial |
* |
| Php7.4 |
Ubuntu |
focal |
* |
| Php8.1 |
Ubuntu |
jammy |
* |
| Php8.3 |
Ubuntu |
devel |
* |
| Php8.3 |
Ubuntu |
noble |
* |
| Php8.3 |
Ubuntu |
oracular |
* |
Potential Mitigations
- Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking.
- D3-SFCV (Stack Frame Canary Validation) from D3FEND [REF-1334] discusses canary-based detection in detail.
- Run or compile the software using features or extensions that randomly arrange the positions of a program’s executable and libraries in memory. Because this makes the addresses unpredictable, it can prevent an attacker from reliably jumping to exploitable code.
- Examples include Address Space Layout Randomization (ASLR) [REF-58] [REF-60] and Position-Independent Executables (PIE) [REF-64]. Imported modules may be similarly realigned if their default memory addresses conflict with other modules, in a process known as “rebasing” (for Windows) and “prelinking” (for Linux) [REF-1332] using randomly generated addresses. ASLR for libraries cannot be used in conjunction with prelink since it would require relocating the libraries at run-time, defeating the whole purpose of prelinking.
- For more information on these techniques see D3-SAOR (Segment Address Offset Randomization) from D3FEND [REF-1335].
References