Malicious PDF — malware analysis report

Static analysis result for SHA-256 c81c81c8714fde74…

MALICIOUS

PDF

40.9 KB Created: 2020-08-31 10:15:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fb4e8800e001170967a3323b2c55e7bf SHA-1: fefce1cac85fdc3af872187e38d6afd042be5803 SHA-256: c81c81c8714fde74500dbe2dfb96a90e9d4aff582a5ba89e63e3950a43b435ef
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains a link to a known malicious redirector, ttraff.ru, which is likely intended to lead the user to a malicious site. The document body is heavily obfuscated and contains what appears to be garbled text, but the presence of the malicious link is a strong indicator of malicious intent. The PDF also contains a large number of links to other PDFs hosted on shopify and static.usrfiles.com, suggesting a link farm or SEO poisoning attempt to mask the malicious redirector.

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.ru/wix?keyword=negative+personality+adjectives
    • https://cdn.shopify.com/s/files/1/0434/9001/7430/files/28554202669.pdf
    • https://cdn.shopify.com/s/files/1/0431/0453/4692/files/17514663030.pdf
    • https://cdn.shopify.com/s/files/1/0433/4492/0734/files/35422962414.pdf
    • https://static.usrfiles.com/ugd/ca9b0a_200ddab56874422ca3fea10877447ea3.pdf
    • https://static.usrfiles.com/ugd/934fc3_ef7e03c1a51642be84d3a9bf7a22e41f.pdf
    • https://static.usrfiles.com/ugd/2f07a1_7d5bc796731147979a45e89bf92a5a7c.pdf
    • https://static.usrfiles.com/ugd/1f2646_d155bd4c51024951a130659530bf26d0.pdf
    • https://static.usrfiles.com/ugd/6290de_bb264b3d337a4989b39693706cd3a3f0.pdf
    • https://static.usrfiles.com/ugd/b98abb_3f450a421f904c728d97f5d6dc67675c.pdf
    • https://static.usrfiles.com/ugd/ce77c6_e6fc94965ca241b494a9fd99408d0c8e.pdf
    • https://static.usrfiles.com/ugd/50c35f_a2931e5374884b829cc1c885c0d95d5a.pdf
    • https://static.usrfiles.com/ugd/3bcfef_8e1cdec398c74922a3985c6645998025.pdf
    • https://static.usrfiles.com/ugd/b0b521_93842b035973453c80bdb0429f61340d.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_off00005bc0.bin
34c73934313e074f8761feefd20ca2e8565611fef1153138487e990ae99e4b6d
pdf-font-stream PDF embedded font (sfnt) at offset 0x5BC0 5448 bytes
font_01_sfnt_off00006e6a.bin
dda6796836c2ccf5ea2f829c7f914555392089e1312fcfefd2cf45bd5193b9dd
pdf-font-stream PDF embedded font (sfnt) at offset 0x6E6A 12948 bytes