Malicious PDF — malware analysis report

Static analysis result for SHA-256 bff15669cf9171e1…

MALICIOUS

PDF

55.8 KB Created: 2020-11-06 08:14:49 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: 0d3dd57b3a54fac765008521028434c2 SHA-1: 1d9dbc2e143754f92c6fc2555a5e01b53a0f598b SHA-256: bff15669cf9171e1463e53925d7b8032dd2386d585cbe364b22dff071e02630b
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous external links, many of which are part of an SEO link farm designed to direct users to potentially malicious content. The primary malicious URL identified is https://trafftec.ru/strik?keyword=bread+slicing+guide+that+does+not+fall+apart, which is also flagged as an image lure for free-download phishing. The ML classifier strongly indicates maliciousness, and the structure suggests a tactic to distribute further payloads or conduct phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://trafftec.ru/strik?keyword=bread+slicing+guide+that+does+not+fall+apart PDF link annotation
    • https://vonubaxuted.weebly.com/uploads/1/3/1/4/131452839/8054379.pdfIn PDF document text
    • https://raxitiladiruwek.weebly.com/uploads/1/3/4/4/134487911/kewowebaxesozusaje.pdfIn PDF document text
    • https://vofixerexelisat.weebly.com/uploads/1/3/4/3/134311693/6876036.pdfIn PDF document text
    • https://xokafewapi.weebly.com/uploads/1/3/4/4/134488510/4123653.pdfIn PDF document text
    • https://vaxajiwozoli.weebly.com/uploads/1/3/1/6/131637631/tokizivofakisejav.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/wilugugo/risk_assessment_guidelines.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7fdd8e90-8bf9-4a7f-bd26-26874a5093fb/misusavadoninomekebisarit.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cdf85257-2e9c-47f9-906a-8ebc8dec3d54/110461701.pdfIn PDF document text
    • https://s3.amazonaws.com/gelawiweza/jipikopijudagubusoxogugaj.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9b65420d-c80e-4634-b192-f74b1e2f4304/lakumunotop.pdfIn PDF document text
    • https://s3.amazonaws.com/bifamomove/plus_size_tulle_skirt_australia.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000820b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x820B 5468 bytes
SHA-256: 3803693504bca3d17e510f8dac942c4f5513e3fe510bf42d0e8d8ed521058755
font_01_sfnt_off0000949f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x949F 11432 bytes
SHA-256: 1fd40be74d7d83e869f79592860bc66acd0127d3bb314a6a36ba3795e7f15436
font_02_sfnt_off0000bb52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB52 16144 bytes
SHA-256: f0a8b786da721c7415a59d91fbce3b20bbb98ea32e48857ac1ff22d53b00ec29