[Secure-testing-team] Bug#885981: exiv2:CVE-2017-18005: Null Pointer Dereference in the Exiv2::DataValue::toLong function

[Salvatore Bonaccorso]

Source: exiv2
Version: 0.24-1
Severity: normal
Tags: patch security upstream
Forwarded: https://github.com/Exiv2/exiv2/issues/168

Hi,

the following vulnerability was published for exiv2.

CVE-2017-18005[0]:
| Exiv2 0.26 has a Null Pointer Dereference in the
| Exiv2::DataValue::toLong function in value.cpp, related to crafted
| metadata in a TIFF file.

The underlying issue according to [2] is that the code is trying to
pring a value in the if statement:

if (Params::instance().printItems_ & Params::prValue)

when this might not be possible. Fix is done via [2].

If you fix the vulnerability please also make sure to include the
CVE (Common Vulnerabilities & Exposures) id in your changelog entry.

For further information see:

[0] https://security-tracker.debian.org/tracker/CVE-2017-18005
    https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-18005
[1] https://github.com/Exiv2/exiv2/issues/168
[2] https://github.com/Exiv2/exiv2/pull/199

Please adjust the affected versions in the BTS as needed, please
double check my assessment for it back to 0.24-1 is done right.
The poc does not trigger, if I'm not completely wrong the affected
code is there.

Regards,
Salvatore