Malicious PDF — malware analysis report

Static analysis result for SHA-256 fbf51908c907724c…

MALICIOUS

PDF

43.4 KB Created: 2020-08-31 11:50:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ef6a45e51d0e66ba2f0e04beab140938 SHA-1: 205184ecfd280fbe94e414e5b3e588e9cc62a4e2 SHA-256: fbf51908c907724c3a259246a109d56c84130876f3069ea205f2499f89bea289
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 academic content. The ML classifier strongly flagged this PDF as malicious. The document body, though heavily obfuscated, contains the URL and appears to be a lure for academic analysis, likely to redirect users to malicious content.

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=como+hacer+un+analisis+literario+de
    • https://static.usrfiles.com/ugd/0d002d_25ac6706699b4cd8b4cb299d6ea07fec.pdf
    • https://static.usrfiles.com/ugd/b8c837_6f1532a2c80a424cbfe51b4caba5ce6c.pdf
    • https://static.usrfiles.com/ugd/18f527_8ad1d2b641344d2699cad7cab273a105.pdf
    • https://static.usrfiles.com/ugd/963627_a179b658e1e74cb5914b78510c354d00.pdf
    • https://static.usrfiles.com/ugd/b8c837_c800a2d639294caeb60323729bd83782.pdf
    • https://cdn.shopify.com/s/files/1/0437/5045/7505/files/bookmark_ipad.pdf
    • https://cdn.shopify.com/s/files/1/0430/2402/3715/files/fearfully_and_wonderfully_made_book.pdf
    • https://cdn.shopify.com/s/files/1/0438/9063/9016/files/osrs_fairytale_2.pdf
    • https://cdn.shopify.com/s/files/1/0430/9496/6429/files/zesolexil.pdf
    • https://cdn.shopify.com/s/files/1/0435/1908/2651/files/5427166460.pdf
    • https://cdn.shopify.com/s/files/1/0430/4856/6941/files/dbt_coping_skills_worksheets.pdf
    • https://cdn.shopify.com/s/files/1/0429/5540/7511/files/263700497.pdf
    • https://cdn.shopify.com/s/files/1/0433/7310/1214/files/nanuzep.pdf
    • https://cdn.shopify.com/s/files/1/0437/7555/7793/files/birbal_stories_in_malayalam.pdf
    • https://cdn.shopify.com/s/files/1/0430/6419/7273/files/shell_credit_card_payment_center.pdf
    • https://cdn.shopify.com/s/files/1/0434/1514/2567/files/bajofosikegexe.pdf
    • https://cdn.shopify.com/s/files/1/0437/6294/2106/files/47552502669.pdf
    • https://cdn.shopify.com/s/files/1/0437/8184/9245/files/pegumujalebuba.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_off00006a7f.bin
529a8797eb8363881aa527a339ef17921220d20417be5b860beabe4853d3e0dc
pdf-font-stream PDF embedded font (sfnt) at offset 0x6A7F 5084 bytes
font_01_sfnt_off00007b94.bin
b3351691cbda52c5590781878c5fc5e16bae5dd278b7669d14c3e827d559fdbc
pdf-font-stream PDF embedded font (sfnt) at offset 0x7B94 10796 bytes