Malicious PDF — malware analysis report

Static analysis result for SHA-256 28c3c39ae3118caf…

MALICIOUS

PDF

38.8 KB Created: 2020-09-01 17:53:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1ad9dcad723c93223631514d11b59da0 SHA-1: f9d1f65f369b153465db44f1d9a323e6de1726c4 SHA-256: 28c3c39ae3118caff1027e7ceb0779fd807840df4a906f695a51b424b067d9fa
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged as malicious by a machine learning classifier and contains a link farm with numerous external PDF links. One of these links, 'https://ttraff.link/wix?keyword=maastricht+v+guidelines', points to known malicious redirector infrastructure. The document body, though heavily obfuscated, contains this URL and other URLs pointing to static.usrfiles.com, suggesting a coordinated effort to distribute malicious content through a link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://ttraff.link/wix?keyword=maastricht+v+guidelines
    • https://static.usrfiles.com/ugd/6290de_140030c6e32d415986fd7ff1155f2463.pdf
    • https://static.usrfiles.com/ugd/9ea91e_5bc06fc7dd29448ca15ab2b560090c58.pdf
    • https://static.usrfiles.com/ugd/3ce946_4563c1aed5514231a4c44527a4959eae.pdf
    • https://static.usrfiles.com/ugd/a2e20a_4dbbeb7636314ddf857c5e152d143465.pdf
    • https://static.usrfiles.com/ugd/5926b4_de539c653af84f29a68587b8b12b67ad.pdf
    • https://static.usrfiles.com/ugd/b8c837_eaac42ce775643ff8ce1e60892284d11.pdf
    • https://static.usrfiles.com/ugd/f967ac_55314e49ce4346fdac405205a108a68b.pdf
    • https://static.usrfiles.com/ugd/b8c837_926c32d8cf9748e6ad86142add143333.pdf
    • https://static.usrfiles.com/ugd/b8c837_48d56d99f5db44099dd19650b14b9f03.pdf
    • https://static.usrfiles.com/ugd/8ba634_4f1a250f60f44dada1f57bbf42d79f46.pdf
    • https://static.usrfiles.com/ugd/b65acf_31e8916063704a7298051e5cbdc511f4.pdf
    • https://static.usrfiles.com/ugd/921909_74b9a9ef64c24417ad7134476b0d7e22.pdf
    • https://static.usrfiles.com/ugd/008e52_cbd814d9865e4eac8b3d4dcd04603dc7.pdf
    • https://static.usrfiles.com/ugd/b8c837_1e8dad06ab114994a11c46421c81dde1.pdf
    • https://static.usrfiles.com/ugd/b7ab08_bba67f00e7834cc2bbbe08304bf9bbd6.pdf
    • https://static.usrfiles.com/ugd/b8c837_6bcb1f5a65bf4a72a1e90f841602bdbd.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000585e.bin
8f148b77112e8815139c9f92befe8958eed9c2061690d39449097d29c978fb67
pdf-font-stream PDF embedded font (sfnt) at offset 0x585E 5264 bytes
font_01_sfnt_off00006a52.bin
4581ea1f2c03336fc907c781dbc10d91d0f357a85648deaae97ef6122459641d
pdf-font-stream PDF embedded font (sfnt) at offset 0x6A52 10688 bytes