Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a3754f9f7c3984c…

MALICIOUS

PDF

77.4 KB Created: 2021-09-19 03:14:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b90eef51ce24a84cdf6a2cf5d06fa739 SHA-1: f0027fa997437cc9731ee4dd9e2dff165852ad51 SHA-256: 3a3754f9f7c3984ca7fc07a9d3c6e9ee5fef032cbd99a7a93a33e1bbdb6b000d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm pointing to multiple compromised CMS upload locations, suggesting an attempt to distribute malicious files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of numerous links on disposable or compromised hosting reinforces the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://ctcinsulator.com/uploads/file/79335502035.pdf
    • http://cmtl.in/uploads/userfiles/file/file/dadexiju.pdf
    • http://bkdesign.ee/userfiles/file/32831630896.pdf
    • http://tavaszitura.eu/userfiles/files/razubupiwuz.pdf
    • http://perles-del-beya.com/userfiles/file/85388348278.pdf
    • https://mimzyonline.com/userfiles/file/mezuvageluzavadudiwokafa.pdf
    • http://cuacuonnhanh.vn/Images_upload/files/97697378789.pdf
    • http://www.tlo.ntou.edu.tw/ckfinder/userfiles/files/mubunemekaxase.pdf
    • http://www.tecnotrefg.it/wp-content/plugins/formcraft/file-upload/server/content/files/16132381a4b8f8---44906225001.pdf
    • http://zoscm.zohukum.com/ckfinder/userfiles/files/19788133138.pdf
    • http://wordtmann.beckbauer.eu/ckfinder/userfiles/files/10773699099.pdf
    • http://shahnawazonline.com/uploads/files/fodita.pdf
    • http://mondoacquapiscine.com/userfiles/files/fujiguse.pdf
    • https://quizai.com/uploads/files/dexamoxutuziwopuvizijigun.pdf
    • https://teater77.nl/userfiles/file/bovit.pdf
    • https://shevtsov-art.com/uploads/files/87051386268.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613e6155a3464---jugawidikuforinupiwe.pdf
    • http://www.iece.in/userfiles/file/38710648233.pdf
    • http://ahkjt.com/upfile/file/5866070743.pdf
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613857f9d0c26---riwexeludupudexuxumu.pdf
    • https://cuatudongnhatrang.com/uploads/files/puvepolazuve.pdf
    • http://oppedisanorobertosrl.com/userfiles/files/88351816932.pdf
    • http://gpmpoolandspa.com/ckfinder/userfiles/files/xudavenumo.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=lego+batman+dc+super+heroes+apk+obb
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c74a.bin
4535920b378b4f79462730bdb09aaad9cac511d5e0537a90f567ee0f3aeb7b58
pdf-font-stream PDF embedded font (sfnt) at offset 0xC74A 18120 bytes
font_01_sfnt_off0000f60a.bin
ea02b3a8058e95c541aa3a19a289a2d4c4000694a6760f4fc12cc3fa5c2ea1f1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF60A 11112 bytes
font_02_sfnt_off00010f60.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F60 16792 bytes