Malicious PDF — malware analysis report

Static analysis result for SHA-256 44d91bca33d8d0a7…

MALICIOUS

PDF

75.3 KB Created: 2021-06-11 01:24:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: b9498320d399abca1b740b9a81a1b511 SHA-1: cd8d35c44a5afba71291acb2e14db3d3b332feff SHA-256: 44d91bca33d8d0a71ac2a714d9b66fb782cd648ad9c9c3e02191b32249969d0a
126 Risk Score

Malware Insights

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

The sample is identified as malicious by ML classifiers and ClamAV, with heuristics indicating it's a link farm on disposable hosting. The embedded URL and document body suggest a lure related to PDF size reduction, directing users to a suspicious domain. While no scripts were explicitly extracted, the PDF structure and embedded URLs strongly suggest an attempt to redirect users to malicious content, likely for phishing or malware delivery.

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://pistant.ru/pbw?utm_term=pdf+size+reducer+100kb PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4393515/normal_6048701d0b4bb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384149/normal_5fd79f2b71eba.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4478123/normal_60184d287e107.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4425784/normal_5fe10d3b519fe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387821/normal_604e28d363fc2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422386/normal_605a36f863a3d.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4388614/normal_5ff179e366a46.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4427091/normal_60606270e57f1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451766/normal_603e6d68b238b.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://tovemubu.pbworks.com/f/how_to_power_up_ecu.pdfIn PDF document text
    • http://famukaser.pbworks.com/f/miro_clash_th_13.pdfIn PDF document text
    • http://funesut.pbworks.com/f/kutawoxebiz.pdfIn PDF document text
    • http://gatunam.pbworks.com/f/43092730782.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b095a63e-c740-4b30-be2e-8fc7a5228636/how_to_mix_curtail_m_herbicide_for_lawns.pdfIn PDF document text
    • http://fevosezew.pbworks.com/f/jebaxewesiruzi.pdfIn PDF document text
    • http://gifavipa.pbworks.com/w/file/fetch/144590742/android_box_remote_programming.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f4f89663-4388-4b43-abcb-23ac80310517/lesson_10_eliminating_wordiness_and_redundancy.pdfIn PDF document text
    • http://podimil.pbworks.com/f/ketamumojoti.pdfIn PDF document text
    • http://sokulus.pbworks.com/f/61643203466.pdfIn PDF document text
    • http://gedelageke.pbworks.com/f/mavokinafugufokopix.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7f9660e5-f82d-447f-a292-317ca46f4430/attack_on_titan_recap_movie_dub.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_off0000eace.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEACE 5224 bytes
SHA-256: 82a9ba81d55cf109808693db0c49a18ba141f56a7e306132f5157d3b85274225
font_01_sfnt_off0000fcb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCB6 10304 bytes
SHA-256: c579022ba00772d686f906611288a03c377b6bde6bb3cea5554abcc5adb488a1

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