Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab8e0d6ff8df9534…

MALICIOUS

PDF

77.5 KB Created: 2021-09-08 10:20:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6de581d8510a7c4f6cefd324bfa8a356 SHA-1: dedef4feff78a1adecb6d153dfebe5ff1d7cf1ae SHA-256: ab8e0d6ff8df95344cb1105faf552b26b85a5d99ce8107536661ffe6e2ca2486
172 Risk Score

Malware Insights

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

This PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a phishing or trojan payload. The presence of embedded JavaScript and links to compromised CMS upload storage suggests an attempt to host and deliver a second-stage payload. The heuristic 'SE_DOWNLOAD_BUTTON' further supports a social engineering lure to trick users into downloading malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 8

  • 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.
  • 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://www.kbstephens.com/wp-content/plugins/super-forms/uploads/php/files/23e02b06a62c5bd2730c51601084c23f/13315869870.pdf
    • https://californiaoptionsrealestate.com/wp-content/plugins/super-forms/uploads/php/files/d4786e23b8f56ebfe06b00b3be94173c/lujojejinoxopusunugi.pdf
    • https://eminencesolutions.in/resources/userfiles/file/35641195507.pdf
    • http://project-lovcen.me/userfiles/file/kifewiwod.pdf
    • http://babywagen24.de/userfiles/file/29774983895.pdf
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160fde991eca4c---samejelumozajakez.pdf
    • https://bishopsalamatkhokhar.org/userfiles/file/kexusiwimurigupamigufepe.pdf
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/48583042960.pdf
    • http://rracc.com/file_media/file_image/file/59245923307.pdf
    • http://tikatalog.sk/_files/file/44977240341.pdf
    • https://www.fibertech1.com/my_content/js/ckfinder/userfiles/files/mexowexapo.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160edc7d25215d---guzapexezepedukuno.pdf
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a458533c28f---tizibirimijip.pdf
    • https://rintrans.com/files/tojegabukakunipokebilumex.pdf
    • https://soba05.org/wp-content/plugins/super-forms/uploads/php/files/307efc974763115c2d49c0604a965493/50678657364.pdf
    • https://marljivo.hr/userfiles/file/11338550160.pdf
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/160956d1c2e8ef---56441998584.pdf
    • http://assotechne.eu/userfiles/files/zulesegijusizipowoxav.pdf
    • http://sunriverps.com/data/editor/file/xuliwaredakezovugulimud.pdf
    • http://expertsystemgroup.com/file_media/file_image/file/37580741038.pdf
    • http://xn--80aamdqpfpr.xn--p1ai/upload_picture/64604135011.pdf
    • http://hornets88.com/clients/56662/File/lurekabab.pdf
    • https://lexcochoralsoc.org/demo/lccs/beta/userfiles/files/tijamizelex.pdf
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8b4181059b---vipezefo.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=kiran+publication+ssc+gk+books+pdf+free+download
    • 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_off0000c1cf.bin
4a0ab9797f7aee5261572ca7ab09db8a9802ac1246d75a42b58bfe4f2a65d832
pdf-font-stream PDF embedded font (sfnt) at offset 0xC1CF 20188 bytes
font_01_sfnt_off0000f671.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF671 16792 bytes
font_02_sfnt_off00010e88.bin
da45f4182c81fd779e06d8d2c473c0b1c5a3c685c83b1b6a33358ea25b4322ba
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E88 11204 bytes