Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa08d0a5530bf5d6…

MALICIOUS

PDF

115.1 KB Created: 2021-07-03 22:46:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b9089ae96c185fd5b8ac0f53d6c62941 SHA-1: e1baa0941dabe5de38337f4d725a94971e0e0621 SHA-256: aa08d0a5530bf5d6bde4fe1046d2c0515cb3fe8c048e71c454e1e24a424cb989
156 Risk Score

Malware Insights

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

The PDF contains a large number of links pointing to compromised WordPress sites, indicating it functions as a link farm. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond what the heuristics reveal.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9885

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://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc15d5d56a---26219213104.pdf
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/415f135e82e760978916cacd30b22f38/31756887745.pdf
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/b784a48acdb6f248401f5c024bbdefdd/letigosasazamisajonemusub.pdf
    • http://getem.plfiles/file/26110649957.pdf
    • http://ty-universe.com/image/files/20210603_040515.pdf
    • https://doganagolosa.it/file/pubopazo.pdf
    • http://szentimresiklos.hu/upload/file/zodofeseronakupe.pdf
    • http://macautemple.com/userfiles/file/pomibixeburobivapaluf.pdf
    • https://eobliecky.sk/userfiles/file/55939231985.pdf
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/904b849bfc18995c38e27c4ba2bf5add/11302859441.pdf
    • https://voicelux.ru/wp-content/plugins/super-forms/uploads/php/files/e837278c969de7eac6e03c84fd95fcc5/20920548073.pdf
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/ealpme3r50pp4jv9nirq4ecc3b/kupelolewuxuvike.pdf
    • http://mygotour.com/FileData/ckfinder/files/20210701_C9681EDB4B548C9F.pdf
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/c197246c5ade8a610f06445978bae16e/xemexozov.pdf
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/160757bab9ae47---10922134013.pdf
    • https://brothers-music.com/ckfinder/userfiles/files/voxotaxakoxiwiwam.pdf
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/16088c08e0f622---gadotatotebupolilip.pdf
    • https://www.asahinafunnels.com/wp-content/plugins/super-forms/uploads/php/files/o7maqpa8bpjs4t9gs85sg7b766/mozawedodube.pdf
    • http://flynewsletter.com/uploads/file/8015730914.pdf
    • http://www.gabrielamaciel.net/images/content/file/vanavumadonexobipopu.pdf
    • https://micro-churches.net/uploads/file/67427096467.pdf
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/8grl6uu21i7uu4p4t33o2cho86/81601622217.pdf
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/e68idu4gep27rrl93hacjnpucj/gonukesexadanapogaxe.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=how+to+convert+cbz+to+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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000101f3.bin
767136c21c164ff9ae1a8d4448296aa9ce46a3d6be41b6cc022ffef88801856f
pdf-font-stream PDF embedded font (sfnt) at offset 0x101F3 10488 bytes
font_01_sfnt_off000119bb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x119BB 16792 bytes
font_02_sfnt_off000131c9.bin
59574eb3dc9532da71997a8c75d158036c8cb8a82c194abce4a085a616cf5c71
pdf-font-stream PDF embedded font (sfnt) at offset 0x131C9 28560 bytes
font_03_sfnt_off000183e5.bin
9dfbb6c0408449339e4b20474bad54c1bf09958e54ffca26cc852be663a9ea1f
pdf-font-stream PDF embedded font (sfnt) at offset 0x183E5 25816 bytes