Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a1350e1bf7ec13a…

MALICIOUS

PDF

70.4 KB Created: 2021-04-08 17:20:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: 0c354897ee6f6c5fbb36976d54a9b3d1 SHA-1: eaccb71005153a203d718f88440fa1a39322ddda SHA-256: 8a1350e1bf7ec13a41f8724127fad129b61d37f7ce1d3665c3d442d38f2fb24e
126 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous external links, many pointing to seemingly legitimate domains but structured to host PDF files, suggesting a link farm or phishing lure. The presence of embedded URLs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic further support the attack pattern of directing users to external, potentially malicious, content. No scripts were extracted, but the overall structure points to a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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/fulakosilukubusovugatupus.pdf In PDF document text
    • https://www.afscme65.org/system/files/webform/baxuwobokorexifiri.pdfIn PDF document text
    • http://www.friendlycc.com/sites/default/files/webform/topevonizudurazot.pdfIn PDF document text
    • https://www.jwico.com/sites/default/files/webform/69174909787.pdfIn PDF document text
    • https://www.blplegal.com/sites/default/files/webform/julojulixizegusu.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/22435641867.pdfIn PDF document text
    • https://www.a1touchsolution.nl/sites/default/files/73086307569.pdfIn PDF document text
    • https://www.ofalloncasting.com/sites/default/files/webform/geguridafaj.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/4264017636.pdfIn PDF document text
    • https://www.mainephilanthropy.org/sites/default/files/lipedoketuparukol.pdfIn PDF document text
    • https://www.woonsocketri.org/system/temporary/webform/danajon.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/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=lysistrata+and+other+plays+pdfPDF link annotation
    • https://thesanfordschool.asu.edu/sites/default/files/webform/moxogugudufagelo.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/bejugejotofetuxiw.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_off0000d786.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD786 5172 bytes
SHA-256: 87d903a7ffceeab232bf1a489d0e447f2f89fe88dd724330f5a0baa0cb001d9c
font_01_sfnt_off0000e924.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE924 10492 bytes
SHA-256: 3d483224155f48725d8f4bd32a803c4a3ebf6644b062b3a2dd26ee1815b7f985