Malicious PDF — malware analysis report

Static analysis result for SHA-256 42dc8d2d83657982…

MALICIOUS

PDF

75.4 KB Created: 2021-09-29 09:07:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fe7165284e0a9133d9a18ff7da7e4a7c SHA-1: 9fbf93915427f469da471fbec9342ea25c213866 SHA-256: 42dc8d2d83657982b97e2ec4e940cd134a744fd8673467c589ba89a2fc74d36c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains an embedded JavaScript stream and a link farm pointing to multiple compromised WordPress upload directories and disposable hosting sites. These links likely serve as redirects to phishing or malware distribution sites, a common tactic for initial access via spearphishing attachments.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://burattinojatek.hu/userfiles/file/73581015954.pdf
    • http://bijverhoeven.nl/uploads/files/laritorutolegilemogu.pdf
    • https://amthanhanhsangchinhhang.vn/upload/files/19058907134.pdf
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/dibinitoxa.pdf
    • http://mansiya.com/uploadfile/files/68697997245.pdf
    • https://tidaksusah.com/contents/files/9121646880.pdf
    • http://baheth24aqari.com/ckfinder/userfiles/files/13584390538.pdf
    • http://bckvalumni.org/userfiles/file/52298887350.pdf
    • http://colleges-in-tamilnadu.com/FCKeditor/userfiles/file/21149021161.pdf
    • https://olympicwroclaw.pl/zdjecia/fck/file/97487911513.pdf
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/ciclfi39o22f0afvu1ou2di5n7/xewumujemeto.pdf
    • https://cyklo-wellness-penzion-palice.cz/content/76717958885.pdf
    • http://ctyrkolky-gamax.cz/data/dokumenty/ridabagivekijol.pdf
    • http://aalzkj.love-mrt.com/upload/files/97689304250.pdf
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139c9f76854c---63374677536.pdf
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/3713f6a2365203aa28558f572ffa66df/86371682074.pdf
    • https://receptabc.hu/images_banner/files/11343907912.pdf
    • https://khabul.mn/mmpa/userfiles/files/44386456976.pdf
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614fe7a2a9bf3---27417085328.pdf
    • http://sz-nuoyi.com/Upload/file/2021091204170615064.pdf
    • http://sbriz.ru/userfiles/file/86563935802.pdf
    • http://www.idukkidiocese.org/files/js/ckfinder/userfiles/files/82513341787.pdf
    • http://billagelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fofusopo.pdf
    • http://3gr-group.com/ci/userfiles/files/96682341893.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=bip+u+watchfaces
    • 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_off0000b9c8.bin
5f51110e1ad93bd57c6acee58f3f3cbd59f1ac3708e81435a8fc44cd4f1e2370
pdf-font-stream PDF embedded font (sfnt) at offset 0xB9C8 10448 bytes
font_01_sfnt_off0000d1c3.bin
30ae61e559760461c6d6c56a726fa103c4f3dc3a4b573504f213112cac37fe28
pdf-font-stream PDF embedded font (sfnt) at offset 0xD1C3 20828 bytes
font_02_sfnt_off00010750.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10750 16792 bytes