Malicious PDF — malware analysis report

Static analysis result for SHA-256 637b4cf7f9027194…

MALICIOUS

PDF

33.0 KB Created: 2020-08-21 12:29:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1b95c84fe4e8364fa5ee7d57f606dd59 SHA-1: f4b271ceb96327a108063e34d605bf64770bf95e SHA-256: 637b4cf7f9027194d5f99c0823133f02169473cdf3d7077ab7eca16f587ac10d
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of embedded links, many of which point to a redirector service (ttraff.ru) that is known to host malicious content. The document body itself contains garbled text but also includes the suspicious URL and a list of other PDF links, suggesting a link farm or SEO poisoning tactic to lure victims. The ML classifier strongly indicated maliciousness.

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/pify?keyword=central+and+inscribed+angles+kuta+software+answers
    • http://files.pureandsimpletruthforyouth.org/uploads/1/3/0/9/130969851/5417217.pdf
    • http://files.workofartstudios.com/uploads/1/3/2/6/132681342/ribilakisuve.pdf
    • http://files.dmaastarkville.com/uploads/1/3/1/4/131452800/gamafexetajabijimu.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0431/0145/4496/files/dedixewanavopebinujow.pdf
    • https://cdn.shopify.com/s/files/1/0433/7513/2824/files/94623792831.pdf
    • https://cdn.shopify.com/s/files/1/0434/2503/8498/files/67293674094.pdf
    • https://cdn.shopify.com/s/files/1/0435/6934/8763/files/80749132551.pdf
    • https://cdn.shopify.com/s/files/1/0429/7873/8335/files/88548450598.pdf
    • https://cdn.shopify.com/s/files/1/0441/0369/6536/files/adultery_paulo_coelho_english.pdf
    • https://cdn.shopify.com/s/files/1/0433/5534/0954/files/bodifulidezowekosuwi.pdf
    • https://cdn.shopify.com/s/files/1/0435/9897/1038/files/68747859881.pdf
    • https://cdn.shopify.com/s/files/1/0433/3250/1656/files/99288041742.pdf
    • https://cdn.shopify.com/s/files/1/0438/2759/3376/files/judaxetilisaduri.pdf
    • https://cdn.shopify.com/s/files/1/0437/0392/6938/files/rudaxiriludimiguf.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/zeranosorijajigafa.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000045b3.bin
83c652b4d3241483b4ff7678835f073a28be6a6f8ee778b1f62a693c84ea47dd
pdf-font-stream PDF embedded font (sfnt) at offset 0x45B3 5392 bytes
font_01_sfnt_off00005821.bin
c53ba74147ddb566cc98514ef3470fbbf679d65da12e918eb55e1cbced7f1a92
pdf-font-stream PDF embedded font (sfnt) at offset 0x5821 8996 bytes