Malicious PDF — malware analysis report

Static analysis result for SHA-256 c135cb80120bc814…

MALICIOUS

PDF

159.3 KB Created: 2021-08-02 12:50:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: a92bf2e70bd4f09372ea2c379f247de7 SHA-1: da27ccf834fcb530200bbdc75173294b79865a2a SHA-256: c135cb80120bc8142962d9166e241b6f8bb814eec3e02dc76c854600b6bf4dbb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to distribute malicious content. The presence of these numerous links and the nature of the hosting suggest an attempt to lure users to external malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://allytemp.ru/uplcv?utm_term=vw+tiguan+workshop+manual+free+download PDF link annotation
    • https://serka.com/serka/upload/files/zotofabajufufipulexiti.pdfIn PDF document text
    • https://canvasations.com/wp-content/plugins/super-forms/uploads/php/files/2mdifet0k1eh4l7evn3q9a57u4/42571157190.pdfIn PDF document text
    • http://thriftstorewebsites.com/flash/thriftstorewebsites.com/file/muzamimiranoduzagotapo.pdfIn PDF document text
    • https://investmentskillsgroup.com/images/userfiles/file/58613753782.pdfIn PDF document text
    • http://doo-san.com/userfiles/file/20210518230414.pdfIn PDF document text
    • http://sumnerclassof1976.com/clients/4/49/49b54eafcc86ae0c30eb104ab8b91c7c/File/rolab.pdfIn PDF document text
    • http://pogservice.ru/userfiles/file/jogobafarujanamiwulos.pdfIn PDF document text
    • https://amrapalispot.com/userfiles/file/78332072194.pdfIn PDF document text
    • http://vtvxm.vn/userfiles/file/zijagitesijakanev.pdfIn PDF document text
    • http://wingmanplanningdemo.com/userfiles/files/lilemoketeguwunovi.pdfIn PDF document text
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/d52e804bfce6fc29d6a6f85442c4b3c9/vobofad.pdfIn PDF document text
    • https://feriaesotericadeatocha.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081c921c935d---sutogepifimotoker.pdfIn PDF document text
    • http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/27b4e300b0477fc530d370a06ad3a00a/mipagepezudawibejox.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b410542faa6---ponigotavinaredisamoxebe.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/bbeucmuomc91h4adce8nculfvo/wumadedu.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/160919461c2eea---78938137187.pdfIn PDF document text
    • http://lsneotek.com/ckupload/files/30475201689.pdfIn PDF document text
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/htj95h41m2hu764tlhd44d3kh3/pulorobizizovem.pdfIn PDF document text
    • https://idfusionllc.com/wp-content/plugins/super-forms/uploads/php/files/36a523427f189bb6f3b1f9ea99f62c46/90337430602.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a31b5e0b962---rotajuzimopisepekaruxabop.pdfIn PDF document text
    • https://micast.de/wp-content/plugins/super-forms/uploads/php/files/d1qtpaecoi4jbdvup53cm5fb3c/22541353198.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/70499465852.pdfIn PDF document text
    • http://eg-connect.com/uploads/editorfiles/file///ragavekova.pdfIn PDF document text
    • https://globalclassic.org/wp-content/plugins/super-forms/uploads/php/files/7eqo2aqv81cc6qnrubggf8nq1v/15996922783.pdfIn PDF document text
    • http://enslev-anlaegsservice.dk/userfiles/file/dakize.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000208f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x208F7 20212 bytes
SHA-256: 1e059c5171ed8b5b32614f674b4798c24a23166a7bcc149a08404c754d428ae5
font_01_sfnt_off00023ab1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x23AB1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000252c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x252C8 11192 bytes
SHA-256: 68d86091e4b59bf73c9cd8be66a7fd47123ee210bed4682af8e2263b460609ae