Malicious PDF — malware analysis report

Static analysis result for SHA-256 82b49a0bbd155ef4…

MALICIOUS

PDF

41.6 KB Created: 2020-08-16 20:44:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f9bb356d6ec02e13cc835d60bdd168ee SHA-1: 04584dcfd4afaa01944e2f62307835758eaf7a04 SHA-256: 82b49a0bbd155ef403a7e0540f0bc9f040f40116ad1d064d5bd180ef5381bc3f
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell T1204.002 Malicious Link

The PDF contains embedded links, with one pointing to a known malicious redirector at 'ttraff.com'. The document body, though heavily obfuscated, includes text suggesting it is a PDF about 'mathematical thinking', a common lure. The heuristic 'PDF_MALICIOUS_REDIRECTOR_LINK' confirms the malicious nature of the redirector, and 'PDF_SEO_LINK_FARM' indicates a large number of external links, many hosted on Shopify, likely to obscure the true malicious destination. The ML classifier strongly supports the malicious verdict.

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/pify?keyword=the+nature+of+mathematical+thinking+pdf
    • http://files.alekstinapoodles.com/uploads/1/3/0/7/130776519/4314976.pdf
    • https://cdn.shopify.com/s/files/1/0428/6873/6166/files/gezabufed.pdf
    • https://cdn.shopify.com/s/files/1/0433/1916/5086/files/67556603674.pdf
    • https://cdn.shopify.com/s/files/1/0429/5157/3657/files/mepafevunomarinalaxupuv.pdf
    • https://cdn.shopify.com/s/files/1/0429/3958/0575/files/kayaking_merit_badge_book.pdf
    • https://cdn.shopify.com/s/files/1/0430/8166/2628/files/56088264693.pdf
    • https://cdn.shopify.com/s/files/1/0435/9972/4702/files/58500231223.pdf
    • https://cdn.shopify.com/s/files/1/0430/1524/1891/files/basketry_merit_badge_pamphlet.pdf
    • https://cdn.shopify.com/s/files/1/0459/8680/7965/files/nidejebosujigababufimitof.pdf
    • https://cdn.shopify.com/s/files/1/0431/5788/0996/files/bhakti_bhojpuri_song_2019.pdf
    • https://cdn.shopify.com/s/files/1/0431/7321/6412/files/kefigu.pdf
    • https://cdn.shopify.com/s/files/1/0435/8491/3565/files/apologize_partition_piano.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_off00006285.bin
e86e2b8af3e2077426912c331b293f282373b14184dec7e69823dc04e89939df
pdf-font-stream PDF embedded font (sfnt) at offset 0x6285 5404 bytes
font_01_sfnt_off000074b8.bin
1c9a767b68cc99c0ccc6c3c7e74ca892df0c6ecf662f27c7b3ed84eae629f1c7
pdf-font-stream PDF embedded font (sfnt) at offset 0x74B8 10368 bytes