Malicious PDF — malware analysis report

Static analysis result for SHA-256 91afbd6e728697cc…

MALICIOUS

PDF

44.6 KB Created: 2020-08-28 04:19:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ca69fcba6f180133a484e372120a41de SHA-1: e7c5ba725fe1e1f6745f4cc792568fa6816239f4 SHA-256: 91afbd6e728697cc8febf332664a188d50cb5bdd01df5bb5245f8cc368d6ca23
152 Risk Score

Malware Insights

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

The PDF contains a significant number of embedded links, with a critical heuristic firing indicating a link farm pointing to known malicious redirector infrastructure. The primary malicious URL identified is https://ttraff.ru/pify?keyword=active+voice+and+passive+voice+rules. The document body, though heavily obfuscated, contains this URL and other Shopify-hosted PDF links, suggesting a coordinated effort to distribute malicious content through a link farm. The ML classifier also strongly flagged this PDF as malicious.

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=active+voice+and+passive+voice+rules
    • http://files.missinternationalaustralia.com.au/uploads/1/3/2/6/132683140/6372502.pdf
    • http://files.wordlyways.com/uploads/1/3/0/9/130968996/182983bdca2ace.pdf
    • http://files.rioblancocattle.com/uploads/1/3/0/8/130874325/4e3c0e13023cf.pdf
    • http://files.sarahmonzonwrites.com/uploads/1/3/0/8/130813528/6711443.pdf
    • https://cdn.shopify.com/s/files/1/0439/6512/0670/files/gadogesigusedivaju.pdf
    • https://cdn.shopify.com/s/files/1/0441/3833/2312/files/fox_sports_mexico_tv_guide.pdf
    • https://cdn.shopify.com/s/files/1/0435/3910/3912/files/76172627308.pdf
    • https://cdn.shopify.com/s/files/1/0435/5037/6100/files/lofewap.pdf
    • https://cdn.shopify.com/s/files/1/0431/3199/4280/files/zajulisawe.pdf
    • https://cdn.shopify.com/s/files/1/0434/5790/4792/files/18290431608.pdf
    • https://cdn.shopify.com/s/files/1/0428/3239/6447/files/36142646750.pdf
    • https://cdn.shopify.com/s/files/1/0463/6285/3531/files/zaxemexenegumezetofajite.pdf
    • https://cdn.shopify.com/s/files/1/0432/4681/3344/files/bemerezev.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_off00006f8a.bin
d039ec3a9961b2e73e61783dc22360534beba413bf0f250eeda67c3e1c9ccdc1
pdf-font-stream PDF embedded font (sfnt) at offset 0x6F8A 5116 bytes
font_01_sfnt_off000080fa.bin
e4f2688eb8837a26004cec7b1f6f85e2d336825258ab6be46924921974c6fa72
pdf-font-stream PDF embedded font (sfnt) at offset 0x80FA 10992 bytes