Malicious PDF — malware analysis report

Static analysis result for SHA-256 4201b3cbbd3bafcd…

MALICIOUS

PDF

70.2 KB Created: 2021-09-28 22:23:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9d0c4ffad29f59426eab02792dcd7183 SHA-1: d9142dc76e9ed52a72b4c9e7e3651837bcc79533 SHA-256: 4201b3cbbd3bafcdb1cca79c7b2796bd29adb1b4f5b4a22776cc0c4c004eda3d
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm for malicious redirection. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. No scripts were extracted, but the PDF structure itself facilitates the redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://wangyiphk.com/userfiles/2501609407.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/47omk485sdmrm8mof2lp0thhf7/55382373419.pdf
    • https://www.wroclawmodelshow.pl/ckfinder/userfiles/files/lewikatizimowilojibewoxu.pdf
    • https://clinicscrm.com/img/files/gibozikuk.pdf
    • https://kudamatsu.org/userfiles/file/tababopulo.pdf
    • http://goodlack.cz/userfiles/file/tabagizezix.pdf
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/1614cd32e89b7d---xigevabenebubususalaxip.pdf
    • https://www.jancsoalapitvany.hu/ckfinder/userfiles/files/dirivaxoratabugoresakefa.pdf
    • https://faktxeber.com/resimler/files/pigunugegesufurexudukiro.pdf
    • http://sungsam.net/userData/board/file/mafafutuxixumupox.pdf
    • http://alcantara.cz/data/file/29820606988.pdf
    • https://advance-pack.com/editor_upload/file/98972131507.pdf
    • http://teleinwestor.com/userfiles/file/sobotilobaxorinuf.pdf
    • http://andreuma.madteam.net/ckfinder/userfiles/files/53369211868.pdf
    • http://tonwen.org/userfiles/file/45273499164.pdf
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161390fe909b02---8644928157.pdf
    • http://www.roosprommenschenckelfoundation.nl/ckfinder/files/files/36004303701.pdf
    • http://thegioixedap.net/upload/files/dabixufesojixuzexomediti.pdf
    • https://nppmaudaha.in/ckfinder/userfiles/files/27692584798.pdf
    • http://jimsclub.net/new/board/img_tinfo/file/20210926173626.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=how+to+get+background+running+application+in+android+programmatically
    • 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_off0000af1f.bin
cd9719a3883671f9d6e63539b358d11eb255440de31a86c10197759326a39dc5
pdf-font-stream PDF embedded font (sfnt) at offset 0xAF1F 11212 bytes
font_01_sfnt_off0000c8f4.bin
8a3b33bcf2821ceb434d4751d468c769660eb1d70abb3ff4b2a838dd11cbec39
pdf-font-stream PDF embedded font (sfnt) at offset 0xC8F4 15884 bytes
font_02_sfnt_off0000f185.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF185 16792 bytes