Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb493ad39a57c294…

MALICIOUS

PDF

71.3 KB Created: 2021-04-11 23:26:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 06c6062293a9f7838fd781d7f1974f83 SHA-1: 6328609ceb2bcca60eb368fd5c49294436460734 SHA-256: fb493ad39a57c294e3770545509079bac400e98b881d09be3e5f59320164f848
126 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests it's part of a link farm designed to mislead users. While no scripts were explicitly extracted, the presence of embedded URLs and the overall structure point towards a phishing or malware distribution attempt, likely leveraging the document's content to appear legitimate.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://ambrose.edu/sites/default/files/webform/42416127327.pdf In PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/mimixinaxeralowevowijut.pdfIn PDF document text
    • https://www.mainephilanthropy.org/sites/default/files/kimakevenowafuxopepasu.pdfIn PDF document text
    • http://portal-mysigma.com/system/files/student-proof/72808970040.pdfIn PDF document text
    • https://www.pharoxglobal.com/sites/default/files/webform/50635107556.pdfIn PDF document text
    • https://www.mothercare.ro/sites/default/files/webform/resumes/49428740932.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/90018929780.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/28695523124.pdfIn PDF document text
    • https://aboss.by/sites/default/files/webform/12404161593.pdfIn PDF document text
    • http://www.muttypawsacademy.com/sites/default/files/webform/vaccines/17184396690.pdfIn PDF document text
    • https://www.blplegal.com/sites/default/files/webform/8025899801.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=minecraft+villagers+not+breedingPDF link annotation
    • https://gradfutures.princeton.edu/system/files/webform/48950823745.pdfIn PDF document text
    • https://ec.europa.eu/eip/agriculture/sites/default/files/webform/vojevo.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ced5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCED5 5184 bytes
SHA-256: 1316b08e777ca6adb042708decd8c7bb8ee275605a0a8862fc87771f3d4067d5
font_01_sfnt_off0000e080.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE080 9984 bytes
SHA-256: a8aa57b183f8fef00b428841178fde4474a366350b1979d44c64f1572bd426f6
font_02_sfnt_off0001028e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1028E 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333