Malicious PDF — malware analysis report

Static analysis result for SHA-256 a65a8c8c30bfc279…

MALICIOUS

PDF

45.4 KB Created: 2020-08-10 10:47:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f70e32f79b19d0a6c6d5a51723e6491c SHA-1: 78f540f3ee122a074b2d0d147279cfc50932856f SHA-256: a65a8c8c30bfc2790cfe8aa9203ceab35f7476661f961a25a6a05d3e02d0d87b
152 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for a malicious redirector link, pointing to `https://ttraff.ru/pify?keyword=anemia+en+ni%25C3%25B1os+pdf+minsa`. Additionally, it exhibits characteristics of a PDF link farm, with numerous external PDF links, many hosted on `cdn.shopify.com`. The ML classifier also strongly flagged this PDF as malicious. The document body contains text related to 'Anemia en niños pdf minsa', suggesting a lure to disguise the malicious links.

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=anemia+en+ni%25C3%25B1os+pdf+minsa
    • http://files.dutzowballpark.com/uploads/1/3/2/6/132696048/8202760.pdf
    • http://files.pivot-nyc.com/uploads/1/3/1/4/131437246/mafebukisoxazow.pdf
    • http://files.mary-ellenfriedland.com/uploads/1/3/1/3/131398094/6151211.pdf
    • https://cdn.shopify.com/s/files/1/0432/5025/3979/files/devejugumilukupelino.pdf
    • https://cdn.shopify.com/s/files/1/0428/4642/1158/files/55429128818.pdf
    • https://cdn.shopify.com/s/files/1/0431/3484/5079/files/zupeto.pdf
    • https://cdn.shopify.com/s/files/1/0437/2771/6520/files/rilanojo.pdf
    • https://cdn.shopify.com/s/files/1/0441/1670/5432/files/30219685268.pdf
    • https://cdn.shopify.com/s/files/1/0431/6626/9600/files/rexunukawizumabadix.pdf
    • https://cdn.shopify.com/s/files/1/0430/6357/4682/files/derawerotubo.pdf
    • https://cdn.shopify.com/s/files/1/0441/1280/6040/files/17837607071.pdf
    • https://cdn.shopify.com/s/files/1/0433/8499/5991/files/lajakafu.pdf
    • https://cdn.shopify.com/s/files/1/0429/3437/0470/files/donon.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_off000070ec.bin
9d18136a138da51c7d95f41fd8ed4ae6d48eedc10f0bbc32e5b8b15ed512aaa0
pdf-font-stream PDF embedded font (sfnt) at offset 0x70EC 5260 bytes
font_01_sfnt_off00008280.bin
fbcebceac9abd4c65cfcdc2748218dce2c54d4eab0d2ed25d6098c035bbe37b8
pdf-font-stream PDF embedded font (sfnt) at offset 0x8280 11096 bytes