Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7efa9c528b237e0…

MALICIOUS

PDF

80.0 KB Created: 2021-09-18 16:51:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3ef470fdee112a3e64158d6120a811d0 SHA-1: 6d71d9fe2e3805f01d02476ff405de203c76eff6 SHA-256: a7efa9c528b237e05528761c8a5a78cbaac83df0fa835635ca0a0f9d58971e6c
192 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which are part of a link farm hosted on disposable domains, suggesting an attempt to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware delivery. The presence of a visual download button lure further supports a phishing or social engineering attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 9

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://kaparatt.com/images/File/48391419325.pdf
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/etu2ccdf9a42l4cot4id770bfm/xowerawitone.pdf
    • http://ljjxmining.com/uploadfile/file///2021091521574685.pdf
    • http://litroshaber.net/resimler/files/moxuturibididuroma.pdf
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613f9ecec2fb2---94922306578.pdf
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/7vu86m7t2tj34djd1r23g0hjs6/dufowemikeg.pdf
    • https://i-chat.tw/js/ckfinder/userfiles/files/vesogababu.pdf
    • http://sjar-tech.com/uploadfile/file///2021090219100850.pdf
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/92d6elf9soeh6huhm0s72uke9q/ruwavus.pdf
    • http://sbsinternationalschool.org/userfiles/file/47163049767.pdf
    • https://net-mex.hu/ckfinder/userfiles/files/fibemagefaforapikus.pdf
    • https://it-remarketing.pl/app/webroot/media/files/34849036096.pdf
    • https://vicotelecom.vn/static/source/images/file/42433851814.pdf
    • https://baruipur.org/ckfinder/userfiles/files/lovuvanibeniko.pdf
    • http://gaudi.tw/upload/files/relowujojerukiwupa.pdf
    • https://www.traitagri-solutions-alternatives.fr/ckfinder/userfiles/files/dovanikajozibujesimev.pdf
    • https://nedimgame.net/calisma2/files/uploads/1040725865.pdf
    • https://dveropolis.ru/upload_picture/78540433299.pdf
    • http://charugarware.com/DEVELOPMENT/charu_garware/uploaded/userfiles/file/dimenogo.pdf
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/1612ffcc8827d0---kewufodejoroz.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=yowhatsapp+download+2018+free+download+apk
    • 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_off0000d323.bin
fcd27613f4c0b859cf1c5fea99ad6675ff4330ea5902f298201546307053064f
pdf-font-stream PDF embedded font (sfnt) at offset 0xD323 17104 bytes
font_01_sfnt_off0000ff8e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF8E 16792 bytes
font_02_sfnt_off000117a5.bin
11a3be7d60b18ab7064ec971b92b86bf5582d8b29536d9aec4e3a37e84b73cd9
pdf-font-stream PDF embedded font (sfnt) at offset 0x117A5 11164 bytes