Malicious PDF — malware analysis report

Static analysis result for SHA-256 a80449f838ee7aac…

MALICIOUS

PDF

37.1 KB Created: 2020-09-01 07:39:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cccb96099d69f76408a1570a8afe3541 SHA-1: 4d4aa419cd5b5a487c57fe8908e71de3f0db589f SHA-256: a80449f838ee7aac559369c83780f6b6d3128edb89b910fe5982b17b2bec66bb
152 Risk Score

Malware Insights

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

The PDF file contains a significant number of embedded URLs, with a critical heuristic firing for a malicious redirector link. Another critical heuristic indicates a PDF link farm, suggesting an attempt to manipulate search engine results or distribute content. The ML classifier also strongly flagged this PDF as malicious. While no scripts were extracted, the sheer volume of links and the presence of a malicious redirector point towards a content-driven attack, possibly for SEO poisoning or to lure users to malicious sites.

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=lagu+charice+one+day
    • https://cdn.shopify.com/s/files/1/0428/4832/1702/files/apprendre_le_russe_lecon_5.pdf
    • https://cdn.shopify.com/s/files/1/0431/0099/5741/files/dusupisivap.pdf
    • https://cdn.shopify.com/s/files/1/0432/3622/9278/files/acura_tsx_manual_transmission_fluid_change.pdf
    • https://static.usrfiles.com/ugd/7198c1_cfe71e60577242dab27eff1f4bd43618.pdf
    • https://static.usrfiles.com/ugd/8b97dd_554d2eaf4ae5486b8eea398b179f6393.pdf
    • https://static.usrfiles.com/ugd/f459ea_b1772f146edb4e53bac0a42b33a4eec0.pdf
    • https://cdn.shopify.com/s/files/1/0429/6717/1223/files/93689600510.pdf
    • https://cdn.shopify.com/s/files/1/0434/1320/9246/files/61848589490.pdf
    • https://cdn.shopify.com/s/files/1/0433/0124/0992/files/najexobekuvejojefodavoja.pdf
    • https://cdn.shopify.com/s/files/1/0434/7943/3382/files/supopa.pdf
    • https://cdn.shopify.com/s/files/1/0432/2839/7727/files/conjunctions_exercises_with_answers.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/43034806536.pdf
    • https://cdn.shopify.com/s/files/1/0435/5604/4951/files/13617875632.pdf
    • https://cdn.shopify.com/s/files/1/0433/7297/0133/files/28547212988.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_off0000549a.bin
335ceeed9de6df9af33c68f93089ff2743c01aa38e35cd3c74ab7cf4d858c16c
pdf-font-stream PDF embedded font (sfnt) at offset 0x549A 5032 bytes
font_01_sfnt_off000065bb.bin
da5ba09deecc18eaab5ec04086779d3df4bdaa30f0744763f3eec51b0da86176
pdf-font-stream PDF embedded font (sfnt) at offset 0x65BB 9992 bytes