Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4cd2ff859901337…

MALICIOUS

PDF

66.6 KB Created: 2021-04-21 18:29:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 88e731e814743f4fac40a09f51db36bf SHA-1: b6496982fb9627089b21aec2fd970e7dc86685ba SHA-256: f4cd2ff859901337dda57e41e19f0b3f4e0a38e3d04e0b1c7c4eb2a849bd2ade
126 Risk Score

Malware Insights

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

The sample is a PDF file flagged as malicious by ML classifiers and ClamAV. It contains numerous embedded URLs, many of which point to unknown or potentially malicious domains, suggesting a phishing or malware distribution attempt. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a large number of links on disposable hosting, further supporting this assessment. No scripts were extracted, but the overall structure and URL distribution strongly suggest a phishing lure.

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 http://cicatsalud.com/html/sites/default/files/webform/buvonajevomowetizebijix.pdf In PDF document text
    • http://www.sumnercountyhospital.org/sites/default/files/webform/vetasitumuwogemukuruv.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/21073527915.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/47116150145.pdfIn PDF document text
    • https://vectorcorp.net/sites/default/files/webform/resume/sowasipaxezok.pdfIn PDF document text
    • http://pilgrimland.com/sites/default/files/webform/resume-uploads/41345860665.pdfIn PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/65810703597.pdfIn PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/55178968397.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/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=legends+and+lairs+traps+%2526+treachery+pdfPDF link annotation
    • https://thesanfordschool.asu.edu/sites/default/files/webform/fapivo.pdfIn PDF document text
    • https://printandmail.princeton.edu/system/files/webform/54002061309.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/rutepirunumobapof.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/simadovi.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_off0000c853.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC853 5068 bytes
SHA-256: c8eec51395bc0806999e79651d6a246198bdee003d609bcebd2d030d8a89c5ff
font_01_sfnt_off0000d9a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9A4 10592 bytes
SHA-256: b8f07f5f90d5a2e6c6aba269a4978d33ec87e0535132fe42b68700b51a9b7892

Open this report in the interactive analyzer, or submit your own file for analysis.