Malicious PDF — malware analysis report

Static analysis result for SHA-256 7f86b499bc558918…

MALICIOUS

PDF

84.8 KB Created: 2021-07-31 11:07:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: dbe834c7d1a2452f26328d777608ddaa SHA-1: 587c81572281e5d6c16e8e20acfe60a4c6e1158c SHA-256: 7f86b499bc558918aaa95fddb21477277baa65404773bcf44def438cccbab742
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file that contains numerous links to external websites, many of which are hosted on compromised CMS platforms or appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the presence of multiple suspicious URLs points to a coordinated effort to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://westernmaki.com/uploads/files/8862748997.pdf In PDF document text
    • https://roomart.uz/ckfinder/userfiles/files/94188333121.pdfIn PDF document text
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16072a27bc884d---44624156125.pdfIn PDF document text
    • http://billsky.ee/files/file/wexaxosonuzezejidegiveb.pdfIn PDF document text
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/77f4d1431561d20fe7b6f8346fcb6b67/matovejozag.pdfIn PDF document text
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083f286cad80---mezup.pdfIn PDF document text
    • http://klinok-saintp.ru/files/11089138833.pdfIn PDF document text
    • http://call.ae/wp-content/plugins/formcraft/file-upload/server/content/files/16080a97e12f47---bepamofexuwiv.pdfIn PDF document text
    • https://hogozaty.com/ckfinder/userfiles/files/46525365420.pdfIn PDF document text
    • http://asfalon.com/__files/file/rijaxejerolagamonoribug.pdfIn PDF document text
    • http://vivaldiskibus.com/FileData/ckfinder/files/20210630_D427E4FFD7E214A1.pdfIn PDF document text
    • http://medicamarsala.it/userfiles/files/tofuti.pdfIn PDF document text
    • https://seataclighting.com/wp-content/plugins/super-forms/uploads/php/files/95e54c3c08370627ddb7c59c982f8a0c/94057366076.pdfIn PDF document text
    • http://thesecurityguardunion.ca/userfiles/files/81082806663.pdfIn PDF document text
    • https://kingwrapcarspa.com/upload/files/25959048728.pdfIn PDF document text
    • http://veterinarioassociatopacinidallatorre.eu/userfiles/files/56481082241.pdfIn PDF document text
    • http://studiotecnicopinto.it/userfiles/files/seferebikinejazisabevugo.pdfIn PDF document text
    • http://camel-republic.com/media/userfiles/files/29856058232.pdfIn PDF document text
    • http://cestovni-postylka.eu/userfiles/file/mujekotemu.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607429ee7ec57---beruve.pdfIn PDF document text
    • https://bhsbeacon.com/FCKeditor/file/31359700084.pdfIn PDF document text
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608ec7003b577---xafuruvuxugubavitavud.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=what+are+the+types+of+usb+connectorsPDF 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_off0000e622.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE622 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fe39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE39 10784 bytes
SHA-256: fc5cc3b155dcd9fcfd5da8af49b9d22267999aa88293f43ac8bb153edc3f6e54
font_02_sfnt_off000116dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116DD 17584 bytes
SHA-256: f3e23ac1bdfd96530ca2c8759c23d6ad94809f5f3b21900009727c390bd95075