Malicious PDF — malware analysis report

Static analysis result for SHA-256 dcb0e80c8d794126…

MALICIOUS

PDF

40.4 KB Created: 2020-08-31 22:45:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: da21b517cbf14264351cfe79028b4da9 SHA-1: 0661fb71508e1b3b10e31016f9858dadd045568c SHA-256: dcb0e80c8d7941266b239202bec43c902997105ea987440967d780d089873781
152 Risk Score

Malware Insights

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

The PDF contains a link that redirects to a known malicious domain, ttraff.com, disguised as an answer key. This is further supported by heuristics indicating a malicious redirector link and a PDF link farm. The ML classifier also strongly flagged this PDF as malicious. The primary attack vector appears to be social engineering via a deceptive link within the document.

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.com/wix?keyword=organic+compounds+worksheet+answer+key
    • https://cdn.shopify.com/s/files/1/0430/6993/1673/files/zajolekavopixipajefesus.pdf
    • https://cdn.shopify.com/s/files/1/0433/6680/9765/files/25535163559.pdf
    • https://cdn.shopify.com/s/files/1/0437/4714/7928/files/tracing_cvc_words.pdf
    • https://cdn.shopify.com/s/files/1/0438/5678/9664/files/pisawelokelowi.pdf
    • https://cdn.shopify.com/s/files/1/0437/9423/5553/files/konodenuvikibuxinurog.pdf
    • https://cdn.shopify.com/s/files/1/0435/7403/4600/files/40083663054.pdf
    • https://cdn.shopify.com/s/files/1/0434/6917/6985/files/rabaje.pdf
    • https://cdn.shopify.com/s/files/1/0431/0853/2380/files/ibps_po_call_letter.pdf
    • https://cdn.shopify.com/s/files/1/0432/6014/9910/files/46840519056.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/vinujavezo.pdf
    • https://cdn.shopify.com/s/files/1/0434/2120/4631/files/pelufonatadunide.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/nojigepinipefonumupitos.pdf
    • https://static.usrfiles.com/ugd/576447_622989201eb44b00b64918b0fe195095.pdf
    • https://static.usrfiles.com/ugd/5ed537_9e0fddd13ed74014ab696fe86067d3bc.pdf
    • https://static.usrfiles.com/ugd/234f58_59362e7bbbae4e4486984effaccf911f.pdf
    • https://static.usrfiles.com/ugd/510a18_ef95ad37262849b589faa946e14791e9.pdf
    • https://static.usrfiles.com/ugd/b8c837_2e9be0217a2c438ca5ca0ecfe9722218.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_off00005df8.bin
584b39b2bc5b809362c1a1fcbfe8b99ececce0ae7b3a796f715efb35df799d4f
pdf-font-stream PDF embedded font (sfnt) at offset 0x5DF8 5740 bytes
font_01_sfnt_off0000716d.bin
6aa91a138e42ef1e6acc9f840a2e8ba56b5655b4b59a843450bc0ecd0246e4c1
pdf-font-stream PDF embedded font (sfnt) at offset 0x716D 10288 bytes