Malicious PDF — malware analysis report

Static analysis result for SHA-256 879d38500fd6b290…

MALICIOUS

PDF

76.5 KB Created: 2021-09-14 22:28:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 35cba642c428f3fee038164ecb0fd7aa SHA-1: 2fb9c73518b3ac7214f158fe654d2d9af9317ce7 SHA-256: 879d38500fd6b290e155b1e62a0793182796fa9d5912834e9846f8aeaf98d2a6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a link farm pointing to multiple compromised or disposable hosting sites, suggesting an attempt to distribute malware or conduct phishing. The presence of numerous external URIs and link farm heuristics strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 6

  • 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 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://vinaaquachem.com/uploads/files/rasepepojepuvalitipaso.pdf
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/1llths98767mhsuoldk6q0ls5d/56586838268.pdf
    • http://keystoparadise.com/userfiles/files/69381918769.pdf
    • http://0575zl.com/userfiles/file/basavekatinumubixusaf.pdf
    • http://yeditepegumruk.com/userfiles/16607306862.pdf
    • https://siam-royal-view.ru/data/files/wojoliwufage.pdf
    • https://aljazeerahdrilling.com/userfiles/files/53510145769.pdf
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/fl3jc1qtfd35rcc9002t1cfh5j/94411467476.pdf
    • https://tuabogadoangel.com/wp-content/plugins/super-forms/uploads/php/files/2ff50ae0188b1cd2be8aa2b7d0b46552/13711615274.pdf
    • http://travelport.pl/userfiles/file/49937890427.pdf
    • http://renovfab-menuiserie.com/userfiles/file/26413637774.pdf
    • https://dpt-mh.com/uploads/news/files/sipojinurarujoxime.pdf
    • http://huefpdf.org/upload/file/7277618883.pdf
    • https://tranhtreo.com/images/ckeditor/files/33730451423.pdf
    • http://bdsps.org/slbdavbatala/userfiles/file/zutoxoxi.pdf
    • https://thehouseproduction.net/file/96840678812.pdf
    • https://qfuse.it/images/uploaded_files/ckfinder/files/1630817212_960575cff9.pdf
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/c1116ef29dc9ed3e6f6c5d85fbbd6660/10723941575.pdf
    • http://hoitruyengiaocodocvietnam.com/uploads/image/files/55895441995.pdf
    • https://assurancemauricie.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133ee343b04b---52387658436.pdf
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/0c75c61dd8d398599ec3de351becbc81/texukunonisabavosizuto.pdf
    • http://michalpavlicek.com/uploaded/file/62068417955.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=pocket+tv+app+download+free
    • https://www.rt9.rspo.org/ckfinder/userfiles/files/55884680728.pdf
    • 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_off0000c6ce.bin
e0dda1464806ca7b024507531d88239f955132088a9af52f68e0549527e5aae7
pdf-font-stream PDF embedded font (sfnt) at offset 0xC6CE 10596 bytes
font_01_sfnt_off0000df3e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF3E 16792 bytes
font_02_sfnt_off0000f750.bin
1894ee568dedce741de673f274ea46c1d55878dc55e01c4483fe94a62f9bf374
pdf-font-stream PDF embedded font (sfnt) at offset 0xF750 17544 bytes