Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b920da84d624cf3…

MALICIOUS

PDF

43.3 KB Created: 2020-08-31 14:48:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e70ef5afc954861dd871deac0c32113b SHA-1: 61d328feaee85327cebeb58b19e564702698e7dd SHA-256: 9b920da84d624cf312ae2150e8aa9a60e7c9ad48567c07928e4a33d096e005d3
154 Risk Score

Malware Insights

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

The PDF file contains embedded links, one of which points to a known malicious redirector. The document body, though heavily obfuscated, contains text suggesting a lure related to a 'weight loss workout plan pdf'. The presence of numerous links to external PDFs, many hosted on Shopify, indicates a link farm strategy, likely to improve search engine ranking for malicious content. The ML classifier 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/wix?keyword=weight+loss+workout+plan+pdf
    • https://cdn.shopify.com/s/files/1/0433/5458/7288/files/printable_doubles_math_facts_worksheets.pdf
    • https://cdn.shopify.com/s/files/1/0430/8808/5143/files/13612460284.pdf
    • https://cdn.shopify.com/s/files/1/0430/0403/5221/files/71723403823.pdf
    • https://cdn.shopify.com/s/files/1/0434/2326/9014/files/xotigofe.pdf
    • https://cdn.shopify.com/s/files/1/0432/5100/7638/files/765205043.pdf
    • https://cdn.shopify.com/s/files/1/0431/1551/1964/files/passive_and_causative_exercises_1_bachillerato.pdf
    • https://cdn.shopify.com/s/files/1/0432/8993/6025/files/mogojix.pdf
    • https://cdn.shopify.com/s/files/1/0429/9148/5091/files/kusisenalalepuwepe.pdf
    • https://cdn.shopify.com/s/files/1/0429/6625/3724/files/vaxevuwupewoxujugofevixof.pdf
    • https://cdn.shopify.com/s/files/1/0434/7396/1126/files/libros_sobre_autolesion.pdf
    • https://cdn.shopify.com/s/files/1/0437/1808/2709/files/28070840561.pdf
    • https://cdn.shopify.com/s/files/1/0432/8960/8360/files/guvelarur.pdf
    • https://static.usrfiles.com/ugd/b8c837_a6ed77a08ea746e39774dbfc7ea47fd7.pdf
    • https://static.usrfiles.com/ugd/2074c9_209fc98a93ee4338b81554886075530f.pdf
    • https://static.usrfiles.com/ugd/b5472a_926ca01694d14c2f8738c8aba4f7c7c7.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_off00006971.bin
e45e1e3db1d730dca868b3964ac50e7340ab27095422043a599bd2b001cc119a
pdf-font-stream PDF embedded font (sfnt) at offset 0x6971 5472 bytes
font_01_sfnt_off00007c25.bin
00e779c4a23828ba6b40750c8ace809a252bb9d61a78e9fdb1641c353c6e6d6d
pdf-font-stream PDF embedded font (sfnt) at offset 0x7C25 10592 bytes