Malicious PDF — malware analysis report

Static analysis result for SHA-256 4376d21da506e727…

MALICIOUS

PDF

37.0 KB Created: 2020-08-12 07:03:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 35f95ab1e5ece46151d1e440d1b55693 SHA-1: 093f93e70858b12275617d0afc09c74777b5098c SHA-256: 4376d21da506e72764e11e13da25d2171e63e3a366259638756cebb6c84a1667
152 Risk Score

Malware Insights

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

The PDF contains a link to a known malicious redirector, ttraff.ru, which is disguised as a search result for an academic book. The PDF_MALICIOUS_REDIRECTOR_LINK heuristic confirms this. Additionally, the PDF_SEO_LINK_FARM heuristic indicates a large number of external links, suggesting a link farm designed to attract traffic. 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=cambridge+english+empower+a1+starter+student+s+book+pdf
    • http://files.bdac.ca/uploads/1/3/0/7/130740522/pekugebe.pdf
    • http://files.decatn.org/uploads/1/3/1/0/131070483/4567643.pdf
    • http://files.laspiritualarts.com/uploads/1/3/2/3/132303264/426802.pdf
    • http://files.dennismichaelfoley.com/uploads/1/3/1/6/131637043/d79b8.pdf
    • https://cdn.shopify.com/s/files/1/0431/3595/9202/files/39253166396.pdf
    • https://cdn.shopify.com/s/files/1/0438/8257/8088/files/banana_bread_recipes.pdf
    • https://cdn.shopify.com/s/files/1/0433/8378/3575/files/freedom_of_religion_apostasy_and_islam.pdf
    • https://cdn.shopify.com/s/files/1/0434/6917/6985/files/capitec_bursary_application_form_2020.pdf
    • https://cdn.shopify.com/s/files/1/0436/8865/7049/files/zusovesedironale.pdf
    • https://cdn.shopify.com/s/files/1/0435/6436/8021/files/wamekakabobekixefefesikew.pdf
    • https://cdn.shopify.com/s/files/1/0432/0008/6180/files/gomujuvokafaxadototixa.pdf
    • https://cdn.shopify.com/s/files/1/0432/2374/4674/files/majurifowevukelipe.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/xidegafizupewutuzu.pdf
    • https://cdn.shopify.com/s/files/1/0431/5050/8194/files/punjab_textbook_physics_9th_class.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000447b.bin
886fd848e81c23b7529b497934503ab9675df22ca7ad17478e37c6bc5636ced1
pdf-font-stream PDF embedded font (sfnt) at offset 0x447B 5708 bytes
font_01_sfnt_off000057ce.bin
be121563639885a233bac5a6fc8f14f98cf1f68453b2cdf6c3f4523aa988fcfb
pdf-font-stream PDF embedded font (sfnt) at offset 0x57CE 9532 bytes
font_02_sfnt_off00007859.bin
1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361
pdf-font-stream PDF embedded font (sfnt) at offset 0x7859 4324 bytes