Malicious PDF — malware analysis report

Static analysis result for SHA-256 1625f18a2de1d251…

MALICIOUS

PDF

35.1 KB Created: 2020-08-06 16:50:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 7ab16b6ef29b30fcc7f0197333a9a320 SHA-1: d72e79cb50c0fbfbf03975a25905674421ec7de9 SHA-256: 1625f18a2de1d2511eb2a39343175f26b8953f1bdbd0fbfc24628e714a9d6c29
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, with at least one pointing to known malicious redirector infrastructure. The document body, though heavily obfuscated, contains URLs that are likely part of a link farm designed to lure users to malicious sites. The ML classifier also 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.cc/wb?keyword=action%20verb%20practice%20pdf
    • http://files.iokokanoa.com/uploads/1/3/2/8/132814611/f474b377ed69.pdf
    • http://tabibala.evolutiondance.ca/uploads/1/3/1/3/131398591/sewabivutinonar.pdf
    • http://files.haraequine.com/uploads/1/3/0/9/130969433/kaloxaje-nuxod.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0437/7152/7325/files/wukuwedon.pdf
    • https://cdn.shopify.com/s/files/1/0447/9365/9543/files/sexy_back_justin_timberlake_lyric.pdf
    • https://cdn.shopify.com/s/files/1/0430/6354/1917/files/benedicta_ward_sayings_of_the_desert_fathers.pdf
    • https://cdn.shopify.com/s/files/1/0431/6217/3602/files/83723733594.pdf
    • https://cdn.shopify.com/s/files/1/0429/3325/6345/files/rinuj.pdf
    • https://cdn.shopify.com/s/files/1/0431/8098/2432/files/46865388425.pdf
    • https://cdn.shopify.com/s/files/1/0438/2782/2749/files/tutagikelejeke.pdf
    • https://cdn.shopify.com/s/files/1/0431/6826/8456/files/26339926374.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/30553092986.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/669297692.pdf
    • https://cdn.shopify.com/s/files/1/0433/2408/0282/files/39197771063.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_off00004ca2.bin
1db4675518703dc0b7e6ed48a6caeeca60afbb5541b8d911550537f5721ca923
pdf-font-stream PDF embedded font (sfnt) at offset 0x4CA2 5128 bytes
font_01_sfnt_off00005e2c.bin
02f47e573ab8801dbff6d58313efd10e0a7244727b5e49c3d5c769e49986c201
pdf-font-stream PDF embedded font (sfnt) at offset 0x5E2C 9876 bytes