Exiv2 is a command-line utility and C++ library for reading, writing, deleting, and modifying the metadata of image files. An out-of-bounds read was found in Exiv2 versions v0.27.3 and earlier. The out-of-bounds read is triggered when Exiv2 is used to write metadata into a crafted image file. An attacker could potentially exploit the vulnerability to cause a denial of service by crashing Exiv2, if they can trick the victim into running Exiv2 on a crafted image file. Note that this bug is only triggered when writing the metadata, which is a less frequently used Exiv2 operation than reading the metadata. For example, to trigger the bug in the Exiv2 command-line application, you need to add an extra command-line argument such as insert. The bug is fixed in version v0.27.4.
Weakness
The product reads data past the end, or before the beginning, of the intended buffer.
Affected Software
| Name |
Vendor |
Start Version |
End Version |
| Exiv2 |
Exiv2 |
* |
0.27.4 (excluding) |
| Red Hat Enterprise Linux 8 |
RedHat |
exiv2-0:0.27.4-5.el8 |
* |
| Exiv2 |
Ubuntu |
bionic |
* |
| Exiv2 |
Ubuntu |
devel |
* |
| Exiv2 |
Ubuntu |
esm-infra/xenial |
* |
| Exiv2 |
Ubuntu |
focal |
* |
| Exiv2 |
Ubuntu |
groovy |
* |
| Exiv2 |
Ubuntu |
hirsute |
* |
| Exiv2 |
Ubuntu |
impish |
* |
| Exiv2 |
Ubuntu |
jammy |
* |
| Exiv2 |
Ubuntu |
trusty |
* |
| Exiv2 |
Ubuntu |
xenial |
* |
Potential Mitigations
- Assume all input is malicious. Use an “accept known good” input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
- When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, “boat” may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as “red” or “blue.”
- Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code’s environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
- To reduce the likelihood of introducing an out-of-bounds read, ensure that you validate and ensure correct calculations for any length argument, buffer size calculation, or offset. Be especially careful of relying on a sentinel (i.e. special character such as NUL) in untrusted inputs.
References