Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a186c6b649cc17f…

MALICIOUS

PDF

71.3 KB Created: 2021-04-23 08:05:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 765e6165a02ca9f5728dec1387feb231 SHA-1: e2c52b1e3560b6c27c12a35bf8ea0714d402d342 SHA-256: 1a186c6b649cc17f5907ed9159a808f84e842bb01627c5d1a44f9b1f41cf8c97
126 Risk Score

Malware Insights

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

The PDF document contains numerous embedded URLs, many of which point to link farms or potentially malicious sites, as indicated by the PDF_SEO_DISPOSABLE_LINK_FARM heuristic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded links are indicative of an attempt to redirect the user to a malicious resource.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://www.enwidth.com/sites/default/files/webform/resumes/60015669747.pdf In PDF document text
    • https://ambrose.edu/sites/default/files/webform/xixarujopotagateregigo.pdfIn PDF document text
    • http://www.pacificsportfraservalley.com/sites/default/files/webform/joxelivoresilawefuxeli.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/fenalop.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/vopezupudatirarib.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/zoxajetuvu.pdfIn PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/26688185713.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=cooking+a+ham+in+an+orion+cookerPDF link annotation
    • https://lib.asu.edu/system/files/webform/dilitopuwivane.pdfIn PDF document text
    • https://ec.europa.eu/eip/agriculture/sites/default/files/webform/95830943344.pdfIn PDF document text
    • https://campusrec.princeton.edu/system/files/webform/xapedejezorim.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dc4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC4A 4972 bytes
SHA-256: 1b35864f7f6ba9fdb447f945f1693759d82083800b68396d1b00a93430b72b42
font_01_sfnt_off0000ed0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED0B 10496 bytes
SHA-256: 438a22cf2deabbca5fb8345cca05df00651273aadaf046d2aa08d414028029c8