Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f879b257f2f124d…

MALICIOUS

PDF

42.2 KB Created: 2020-08-18 15:26:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 27f32604b9480a37074667a40cdc434c SHA-1: 64afdf85c19a6cdcd0d2ab43306c89dbc0661d83 SHA-256: 8f879b257f2f124ddcb417e3334470da0d55c69c5fe6147bdf496622559fd69e
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains embedded links that point to a known malicious redirector, ttraff.cc, which is disguised as an application form. The document body, though heavily obfuscated, contains text related to 'bitsat 2019 application form official website' and includes the malicious URL. The presence of a link farm with numerous PDFs hosted on Shopify further suggests an attempt to manipulate search engine results or distribute content. The ML classifier also strongly indicated maliciousness.

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.cc/pify?keyword=bitsat+2019+application+form+official+website
    • http://files.hcfcorp.org/uploads/1/3/0/7/130776449/6f7a311670f.pdf
    • http://files.joyneruphorsemanship.com/uploads/1/3/2/7/132740296/jezutunojepor.pdf
    • http://files.littlecrabastrology.com/uploads/1/3/1/1/131164557/467fb4db63b7c0.pdf
    • https://cdn.shopify.com/s/files/1/0431/2665/3079/files/alarm_check_valve_assembly.pdf
    • https://cdn.shopify.com/s/files/1/0430/4686/3005/files/vinupogifi.pdf
    • https://cdn.shopify.com/s/files/1/0433/0664/7717/files/kakuxow.pdf
    • https://cdn.shopify.com/s/files/1/0437/7785/1543/files/subukukevesibawevatefusu.pdf
    • https://cdn.shopify.com/s/files/1/0429/6101/0842/files/fapuxevewegewesorisu.pdf
    • https://cdn.shopify.com/s/files/1/0428/5733/2895/files/ladud.pdf
    • https://cdn.shopify.com/s/files/1/0430/9814/4932/files/fabidevejedogasum.pdf
    • https://cdn.shopify.com/s/files/1/0429/9423/7593/files/29918421177.pdf
    • https://cdn.shopify.com/s/files/1/0430/8323/5489/files/pajabilagopevaman.pdf
    • https://cdn.shopify.com/s/files/1/0431/9074/7295/files/10127903822.pdf
    • https://cdn.shopify.com/s/files/1/0434/6331/1512/files/78671451806.pdf
    • https://cdn.shopify.com/s/files/1/0430/1121/1425/files/2020_calendar_blank.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_off000063ac.bin
37d123b3e240359ebd39365862c4079311525d3c74772611899f82026bc446cd
pdf-font-stream PDF embedded font (sfnt) at offset 0x63AC 5924 bytes
font_01_sfnt_off000077c3.bin
3116421c5c43f2b2ed17a8b10c251b1d5ef281fd043fdfbe2aa3f1fabb2fa249
pdf-font-stream PDF embedded font (sfnt) at offset 0x77C3 10776 bytes