Malicious PDF — malware analysis report

Static analysis result for SHA-256 0c4f21f6150715ae…

MALICIOUS

PDF

87.4 KB Created: 2021-09-06 03:32:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: beba586bf9c8ea61423b425c467286e0 SHA-1: fa88751726eb608abf8dc41192148bc070437eb9 SHA-256: 0c4f21f6150715ae4f5ad62e363026c88a38c28988cca1aa5c375a8b4d9b4d27
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The ML classifier and ClamAV both flagged this PDF as malicious, with ClamAV identifying it as a phishing trojan. Heuristics indicate the PDF contains a link farm pointing to compromised CMS upload storage and disposable hosting, suggesting an attempt to redirect users to malicious sites. While no scripts were directly extracted, the PDF structure and URL patterns are consistent with phishing lures or malware droppers.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://yingzhaoliuart.com/upload/file/govogikozavo.pdf In PDF document text
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5bc2a1d2d---guvejuzulid.pdfIn PDF document text
    • https://socialchangefactory.org/wp-content/plugins/super-forms/uploads/php/files/f1d5647f77788f337bc0fd715e91e54e/beririxelusozux.pdfIn PDF document text
    • http://sea-cruise.ru/ckfinder/userfiles/files/4713647536.pdfIn PDF document text
    • https://chaplains-camps.org/upload_picture/file/tisoxojuguzavujewakarov.pdfIn PDF document text
    • https://www.penyembuhanholistikreiki.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b0a6066f26---77426851561.pdfIn PDF document text
    • http://cke.hk/userfiles/debiniwaduxabokemukip.pdfIn PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607c01a3ec225---62258227405.pdfIn PDF document text
    • http://marketherballize.com/ckfinder/userfiles/files/jewubefa.pdfIn PDF document text
    • https://asoriofrio.org/ckfinder/userfiles/files/32868684094.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/47faf47c54e280321bc55f0155325838/xulonufivaginojibiziki.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/xesejo.pdfIn PDF document text
    • http://niestachow.pl/data/aktualnosci_imgs/file/98445469242.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160e1198d788b4---pujetukisuzukotuxasizug.pdfIn PDF document text
    • https://brianhigbielaw.com/UserFiles/file/zuvotifenorog.pdfIn PDF document text
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/5bf0ae3000fb74e4555b239f1cf0e3cb/9520956600.pdfIn PDF document text
    • http://jiehuist.com/userfiles/files/91886965341.pdfIn PDF document text
    • http://luberoff.com/userfiles/file/93888694566.pdfIn PDF document text
    • http://jhdljz.com/userfiles/file/1624268982.pdfIn PDF document text
    • https://fatheragneliti.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e488698bb8b---widururilurovibe.pdfIn PDF document text
    • https://munord.com/wp-content/plugins/super-forms/uploads/php/files/f5e5c90b0ebd304005e35263a23b6253/83648804735.pdfIn PDF document text
    • http://alpanelektrik.com/depo/sayfaresim/file/femofubemubonod.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-5-21/20210521094234322819.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075c6939eada---fafixigasizoput.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=public+toilet+design+plan+pdfPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ef89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF89 18268 bytes
SHA-256: 48036af529d25b8897417f57e508af36c5e276201793e52f21adb453abe7a2f3
font_01_sfnt_off00011efa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EFA 10936 bytes
SHA-256: a965554b50a42c9e58e1bf05a885418827c7c21f605b2ec047fc8eabc37008c5
font_02_sfnt_off00013807.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13807 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1