Malicious PDF — malware analysis report

Static analysis result for SHA-256 7432c611f6e2468f…

MALICIOUS

PDF

83.6 KB Created: 2021-07-27 18:13:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 85813cb2691df0e1a2385078b7f5e346 SHA-1: 610ae6c9f94e5b03c97e9f9b9727fa954f5fe780 SHA-256: 7432c611f6e2468f47801559346e04f94e7b880b38eefb5a820ba669f2bfe69e
196 Risk Score

Malware Insights

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

The sample is identified as malicious by ML classifiers and ClamAV, with heuristics indicating it's a remote-support tool lure. The document body is heavily obfuscated, but the presence of numerous external links, some pointing to compromised CMS uploads, suggests an attempt to redirect users to malicious content or downloads. The primary attack pattern involves social engineering to trick users into installing potentially harmful remote access software.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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
  • Remote-support tool lure high SE_REMOTE_SUPPORT_LURE
    Document instructs the user to install, open, or connect with a remote-support tool such as AnyDesk, TeamViewer, Quick Assist, or ScreenConnect — high-risk in an unsolicited document
  • 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 http://narnivet.com/userfiles/files/75788587188.pdf In PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608337176618a---83016481258.pdfIn PDF document text
    • http://auto-spec.ca/fck/file/xifekagovobutosexogerumun.pdfIn PDF document text
    • https://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/rdrfcdt05pusvrusfn00i6ttbi/30307135051.pdfIn PDF document text
    • http://aberdeeneyes.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a9509cad7b8---38445537626.pdfIn PDF document text
    • https://jerseyshorepirates.com/userfiles/files/tafux.pdfIn PDF document text
    • http://ingenermarket.ru/userfiles/sugiparukiwozoxab.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ac5fe710ebd---sujetalujupowi.pdfIn PDF document text
    • https://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/5b64b057be1c7ca2ff6823ad20df5786/77102998126.pdfIn PDF document text
    • https://fiberglasssupplydepot.com/userfiles/files/7439938340.pdfIn PDF document text
    • https://kassa-evotor.ru/wp-content/plugins/super-forms/uploads/php/files/r6q6clonq13n7tdljanfkq67ui/livizenoleru.pdfIn PDF document text
    • http://narnivet.com/userfiles/files/wabumipinenojatejenaxoz.pdfIn PDF document text
    • https://birsamundapark.in/userfiles/files/42071781218.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094bd1f33dfd---80164735887.pdfIn PDF document text
    • https://www.osteopathe-montpellier-sud.fr/ckfinder/userfiles/files/silaranuxunomejazus.pdfIn PDF document text
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/16086a8067e801---tabojunimatinuzuvafuti.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/butqahke0jq06071ej2h8igq9g/veburumisuriw.pdfIn PDF document text
    • https://www.ptlittleflower.org/wp-content/plugins/super-forms/uploads/php/files/hmng29f3hsenhj9q92k0c04rg3/vowekatonobeb.pdfIn PDF document text
    • http://archimax.ch/dynamic-images/cms/file/natibidezik.pdfIn PDF document text
    • http://inspiredindianfoundation.org/uploads/rupomododagufogawepikifis.pdfIn PDF document text
    • http://anonelectronics.com/admin/fckeditor/editor/filemanager/connectors/php/upload_jpg/file/202107221550381498.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/16087af5c42198---zazelemesake.pdfIn PDF document text
    • https://clumba-indoor.ru/files/files/kovavonevu.pdfIn PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc5cfc92eb---14221743347.pdfIn PDF document text
    • https://www.reachcast.ca/wp-content/plugins/super-forms/uploads/php/files/44a98e3081923c4185eb423f223833b6/6996273245.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=times+tables+worksheets+printable+pdfPDF link annotation
    • 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_off0000e4d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4D0 16508 bytes
SHA-256: 6b0b927e6337660835ded9fa796db643344d7ea74f798ae6f287e9727187bcf1
font_01_sfnt_off00010f74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F74 11044 bytes
SHA-256: a68d8afb46339bbd9fab93bde1a9c2476a62479bf59ba932906721afe616bfb2
font_02_sfnt_off000128d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128D2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1