Malicious PDF — malware analysis report

Static analysis result for SHA-256 71cd710bea1be098…

MALICIOUS

PDF

56.3 KB Created: 2020-08-19 00:20:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d4f755e2ac3dcaff03a3ec6d9141bba6 SHA-1: 3d162abea2af64cb01a04efd8a598f9a4ba58c3a SHA-256: 71cd710bea1be0985b7d204ec4eb305a6644127e540cff7137be38fe6c4a924b
154 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with one identified as a malicious redirector. The document body, though obfuscated, contains text suggesting a lure related to a 'classroom observation report conclusion' and points to the malicious URL. The presence of a link farm and a critical heuristic firing for malicious redirector links strongly indicates a phishing or scam attempt.

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=classroom+observation+report+conclusion
    • http://tatinisam.emmafisk.co.uk/uploads/1/3/1/4/131407921/3552422.pdf
    • http://files.cornerstoneferndale.org/uploads/1/3/1/1/131164047/kexigiketin-fivutuz-tozufidoju-dipunolizi.pdf
    • http://files.regentlaw.net/uploads/1/3/1/1/131164386/45252e8b1475.pdf
    • http://files.wheeler-fabrics.co.uk/uploads/1/3/1/4/131406430/5814563.pdf
    • http://zuper.diggersite.com/uploads/1/3/1/3/131380600/kazajutusise-dafipabu-nuful-velomufagizana.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0433/9597/3283/files/felezimirajekifo.pdf
    • https://cdn.shopify.com/s/files/1/0437/1687/0309/files/98989339241.pdf
    • https://cdn.shopify.com/s/files/1/0431/7695/1974/files/86030198540.pdf
    • https://cdn.shopify.com/s/files/1/0459/6033/1423/files/bryson_tiller_patient.pdf
    • https://cdn.shopify.com/s/files/1/0431/5031/1579/files/nba_live_2007.pdf
    • https://cdn.shopify.com/s/files/1/0433/9266/3702/files/kerusonomo.pdf
    • https://cdn.shopify.com/s/files/1/0434/0062/6325/files/rozalotesavivanapen.pdf
    • https://cdn.shopify.com/s/files/1/0435/8979/5998/files/20870393885.pdf
    • https://cdn.shopify.com/s/files/1/0427/9477/8791/files/tebiduwiwomazugu.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_off00009fa7.bin
05f71a8d075628d50feff7dc0c6c88f4056c6a314da470b365b5dc143ee4e108
pdf-font-stream PDF embedded font (sfnt) at offset 0x9FA7 5184 bytes
font_01_sfnt_off0000b139.bin
83f5028cbdff6023ec4345e3a5d361c0a86542da6b6d29665110083a6a0c5e06
pdf-font-stream PDF embedded font (sfnt) at offset 0xB139 10372 bytes