Malicious PDF — malware analysis report

Static analysis result for SHA-256 05f23755cff1bb28…

MALICIOUS

PDF

81.3 KB Created: 2021-09-12 05:27:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 7a30531f3f1581f0adf0fd160c8125b4 SHA-1: da105b66b0fd8e4c9b44d6fbcb0c3b157b3487b4 SHA-256: 05f23755cff1bb28ae5a702bd7954dc921bbaa166b2c4b06365dd752941bef9a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs that point to compromised WordPress uploads and disposable hosting, suggesting it functions as a link farm. The primary purpose appears to be directing users to external malicious sites, likely for phishing or malware distribution, which is consistent with a spearphishing attachment attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://crewmak.ru/uplcv?utm_term=jumanji+2017+123movies PDF link annotation
    • http://ssteelelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/91365800668.pdfIn PDF document text
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/1e4588d7b2564c304c8705605baa28c0/sipigaziwutubipuminebo.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/93820389cd42c2d3e2de3f2f420e3a5f/notekinunesowuvafuxupebok.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/16135aeb95d208---golozegatur.pdfIn PDF document text
    • https://adtw1.elfjane.com/ckfinder/userfiles/files/95091463543.pdfIn PDF document text
    • https://www.esicm-old.org/admin/lib/ckfinder/userfiles/files/20603291438.pdfIn PDF document text
    • http://wdnederland.nl/file/pikinukasafisuzivifixire.pdfIn PDF document text
    • https://zlatartopalovic.rs/files/39796932742.pdfIn PDF document text
    • https://codecs.ro/images/file/18248370871.pdfIn PDF document text
    • http://tantusmarina.com/UserFiles/file/72556292711.pdfIn PDF document text
    • https://mystruggle.uk/indigo/ckfinder/userfiles/files/kanuralubap.pdfIn PDF document text
    • http://zhihepvb.com/upload/ckimg/files/202109031952133499.pdfIn PDF document text
    • https://tsydesign.com/userfiles/jws/files/jatojobuvivetupijebuvifej.pdfIn PDF document text
    • http://www.moyekolodin.com/files/52190130307.pdfIn PDF document text
    • https://transturist.ba/ckeditor/ckfinder/files/files/26778318862.pdfIn PDF document text
    • http://top-rubber.com/admin/fckeditor/editor/filemanager/connectors/upload/file/30023809851.pdfIn PDF document text
    • http://bjsixiang.com/jingkelun/userfiles/files/20210908141008.pdfIn PDF document text
    • https://www.akilciilacdernegi.com/ckfinder/userfiles/files/8047816982.pdfIn PDF document text
    • http://immobilieninvestors.net/userfiles/file/gabisu.pdfIn PDF document text
    • http://fc-junajted.com/upload/datoteke/6121773680.pdfIn PDF document text
    • https://butyfarm.mm520.net/userfiles/files/tegoxopek.pdfIn PDF document text
    • https://aicpwdosaeast.com/ckfinder/userfiles/files/89236318710.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://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_off0000d435.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD435 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC4C 10828 bytes
SHA-256: 1838ce69b8ea71c02b0871df8b072bf64414f3c459c677338d0670c7d9975533
font_02_sfnt_off00010562.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10562 19764 bytes
SHA-256: fa7a7793dab11c6e2bcc050f87ea76b8221e0c09b691d299c5bab248dbf00abf