Malicious PDF — malware analysis report

Static analysis result for SHA-256 757eef5ebbd4ce7d…

MALICIOUS

PDF

42.8 KB Created: 2020-09-01 06:13:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: de8240cdd368441708c4bf44fb378156 SHA-1: 2e98bd11ce43751b5b00738a1401f99fad44bb34 SHA-256: 757eef5ebbd4ce7d2a1cbfb7f3934176b89def0f610a5c6894969d0df6f5d575
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a mass external link farm, with one primary URL identified as a malicious redirector. The document body, though heavily obfuscated, contains text related to an 'identifying nouns worksheet' and the malicious URL, suggesting a lure to trick users into clicking the link. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a phishing or redirection attack.

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.club/wix?keyword=identifying+nouns+worksheet+with+answers
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0428/9075/6259/files/niziwexomugitu.pdf
    • https://cdn.shopify.com/s/files/1/0429/7952/4759/files/45490487931.pdf
    • https://cdn.shopify.com/s/files/1/0428/8492/3555/files/13755007732.pdf
    • https://cdn.shopify.com/s/files/1/0437/2732/3301/files/pesipisokolaligebo.pdf
    • https://cdn.shopify.com/s/files/1/0439/1239/6968/files/96577811473.pdf
    • https://cdn.shopify.com/s/files/1/0435/8638/8123/files/pop_goes_punk_torrent.pdf
    • https://cdn.shopify.com/s/files/1/0437/8945/1416/files/hand_job_videos.pdf
    • https://cdn.shopify.com/s/files/1/0431/7744/3483/files/48817510037.pdf
    • https://cdn.shopify.com/s/files/1/0434/6108/3301/files/jejononufite.pdf
    • https://cdn.shopify.com/s/files/1/0430/8746/2551/files/assistant_commandant_question_paper.pdf
    • https://cdn.shopify.com/s/files/1/0431/3071/6322/files/fedogizibovatag.pdf
    • https://cdn.shopify.com/s/files/1/0436/3422/9398/files/zudimavutinazodunotibuwid.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006988.bin
473ff4bfc34e4581b8cfb8be16efdb855c347ac9c8e9d24a31e12c0f5314cce5
pdf-font-stream PDF embedded font (sfnt) at offset 0x6988 5332 bytes
font_01_sfnt_off00007bc8.bin
54929ff28f74d5221d95383ce79fec7232d027a297f043d36a05b4d5a43a5aa1
pdf-font-stream PDF embedded font (sfnt) at offset 0x7BC8 10220 bytes