Malicious PDF — malware analysis report

Static analysis result for SHA-256 d23f9a53296fa3bd…

MALICIOUS

PDF

77.7 KB Created: 2021-09-06 16:44:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 78c00be2d68537fb3a3f9b6a2ca6e943 SHA-1: 85038a6a857add32dcb5a403371fe8852a41f47c SHA-256: d23f9a53296fa3bd303cf1f3f72b0a5d05474d09570436bd02b6c56b51286f4e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to lure users to malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery through these links. No scripts were extracted, and the document body was unreadable, but the URL structure and heuristic firings are sufficient for this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

Heuristics 6

  • 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.
  • 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://maslag.eu/userfiles/file/mazanakajubasoluri.pdf In PDF document text
    • http://www.depomatrial.com/file/60361017074.pdfIn PDF document text
    • https://lightingsystemscol.com/wp-content/plugins/super-forms/uploads/php/files/cd5ca2e326b84fbc811f37d3537bc80e/ganelumin.pdfIn PDF document text
    • https://lombardpruszkow.pl/local/userfiles/file/64720829479.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adb610bc14e---13921489258.pdfIn PDF document text
    • https://www.wflorlando.com/wp-content/plugins/super-forms/uploads/php/files/cf2af57eac500a458c2021bfcc5bc5fe/35065950886.pdfIn PDF document text
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f0d824cff5---32966314131.pdfIn PDF document text
    • http://ritadas.in/userfiles/file/nefavodak.pdfIn PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16125a1e6e9e3d---72596114663.pdfIn PDF document text
    • https://latgalesamatnieki.lv/files/file/30970085283.pdfIn PDF document text
    • https://rinducm1.com/contents//files/papiw.pdfIn PDF document text
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/174de554a79ccce74fb5587a45eac4d1/1510374268.pdfIn PDF document text
    • https://rhuyscampingcar.fr/images/files/pukalaminezifa.pdfIn PDF document text
    • https://cuisinescartier.ca/upload/editor/file/75351635817.pdfIn PDF document text
    • https://alternativecarrepair.com/userfiles/file/wiwujuwapewevepewomufono.pdfIn PDF document text
    • http://goodmix-psc.com/userfiles/files/3217899837.pdfIn PDF document text
    • https://bibliothequedesarts.ch/ckfinder/userfiles/files/paxapajekaf.pdfIn PDF document text
    • http://fuerst-architects.com/uploads/file/1795637980.pdfIn PDF document text
    • http://expertcomptablecourreges.fr/michel_courreges/userfiles/file/89280612898.pdfIn PDF document text
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/mgsau5q31ac4mi4ophqor77oj6/bagaj.pdfIn PDF document text
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b160814cc58---gevepowuti.pdfIn PDF document text
    • https://sjalikave.hu/pictures/file/ronotasalaboren.pdfIn PDF document text
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/e7f004715d5fa7500ed5118949e6c5c0/dibezufavino.pdfIn PDF document text
    • http://concilianavarra.com/userfiles/files/16092264000.pdfIn PDF document text
    • http://sibstroiexp.ru/userfiles/file/bewabikazuziredimaxafoz.pdfIn PDF document text
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607849bf6dca9---10124953830.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=maths+scheme+of+work+pdfPDF link annotation
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/953ee089ddfcec7e06e059f6e36bcd0c/70374801019.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_off0000cae3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAE3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e2f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2F5 17332 bytes
SHA-256: 33e4939c5f76aa700cd8b83cdfe5c180694f786c093ec950b63b3198fab33fdf
font_02_sfnt_off00011019.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11019 10812 bytes
SHA-256: 9409ac9dffc236e08918ca1147ef0c9fe009634fcd773b8d242cf1a8b5688357