Malicious PDF — malware analysis report

Static analysis result for SHA-256 e88796fab8cbc290…

MALICIOUS

PDF

81.7 KB Created: 2021-09-01 20:46:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ac5d537c9692963d07e4a5bfa2e9211d SHA-1: 3d751a1d03e3a2f2c3ed6e6ab30b48aa7119b9e1 SHA-256: e88796fab8cbc2904a393eb8e3199f90323ec4f525dc67ee0da67060d3e756da
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external links, many pointing to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection or obfuscate the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://all-pass.com/folder/editor/file/jimijujekutuwa.pdf
    • http://infinity-pro.ru/userfiles/file/89722930575.pdf
    • https://santehsevast.ru/userfiles/files/13972895815.pdf
    • http://biaikatolikus.hu/files/file/repuxan.pdf
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/844ae1baf914eb7243540c97ecb6b8dc/81539065902.pdf
    • https://maturana.cl/upload/file/17000721076.pdf
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/0ic4mbnc020p9ku0knef2n2r8k/39711056804.pdf
    • https://hogies.com/includes/template/uploads/file/50659066035.pdf
    • https://afd.me.uk/wp-content/plugins/super-forms/uploads/php/files/mrrsdjr89sa2nsd3tvd2o5aegs/kaxiniga.pdf
    • https://bustotoronto.com/userfiles/file/99866597731.pdf
    • https://himalayanwanderer.com/himalayan/userfiles/files/56824224221.pdf
    • https://pecsikult.hu/files/file/55315049634.pdf
    • http://pogservice.ru/userfiles/file/fularov.pdf
    • https://shevtsov-art.com/uploads/files/merapexipuje.pdf
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c78098a4969---42752933776.pdf
    • https://ozmutludokum.com/userfiles/file/58247433347.pdf
    • http://cuborh.com/natelinhanew/js/ckfinder/userfiles/files/karuwav.pdf
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/160f5d5bc0cd2b---50862854351.pdf
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160f6aafcf30ec---44167067662.pdf
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/1310769a90332255a1e5ab15288fd5da/zufuzalebovisox.pdf
    • https://carpanea.it/wp-content/plugins/super-forms/uploads/php/files/772dd4aabb070359ede5aa874ac08d62/70627421563.pdf
    • http://moyamoya.center/images/hand_uploaded/files/sufaj.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=protech+model+520+thermostat+manual
    • 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_off0000d912.bin
4f531e53179045930cffda8b702ddab8eb6b67aead7d9979061584f59f125a86
pdf-font-stream PDF embedded font (sfnt) at offset 0xD912 18224 bytes
font_01_sfnt_off000107c7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x107C7 16792 bytes
font_02_sfnt_off00011fde.bin
c8320cde0117438999cca8f27bc290752a8fa63dcc5244faf58b5458e45ac0ec
pdf-font-stream PDF embedded font (sfnt) at offset 0x11FDE 11020 bytes