Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ab513c3a3f55197…

MALICIOUS

PDF

87.0 KB Created: 2021-09-16 09:59:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 660025bec41f78996d1ceb74405c5b48 SHA-1: 3ed900651d0e3ebfa520d080b3f81ef928ba28ed SHA-256: 4ab513c3a3f551970e526491b4ef5d09f57c8c35ec355dce463832afdb569797
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS upload directories or are part of a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution via these links. The presence of embedded JavaScript suggests an attempt to execute code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613f8858d0adb---zizew.pdf In PDF document text
    • http://beetsom.com/PROGRAM_FCKeditor_UserFiles/file/90058471361360113579f0.pdfIn PDF document text
    • https://sskundal.com/userfiles/file/zivatorufemoboxiruviluk.pdfIn PDF document text
    • http://atmaircenter.com/lb/userfiles/files/lofisedafusiwodofipe.pdfIn PDF document text
    • https://educhina.mn/editor/files/revofiraxok.pdfIn PDF document text
    • http://twfindia.in/userfiles/files/natevoraxobazegutofube.pdfIn PDF document text
    • http://www.frank-diagn.hu/userfiles/files/juxisovotabapujarapesu.pdfIn PDF document text
    • http://parentini.it/userfiles/files/57207812818.pdfIn PDF document text
    • https://semangkamerah.com/contents/files/43337614141.pdfIn PDF document text
    • http://ajarnveerapong.com/UserFiles/file/23391387685.pdfIn PDF document text
    • http://foxgraphics.paulsfashion.in/files/50251996071.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1613c2f496c459---73324232326.pdfIn PDF document text
    • http://docando.es/js/ckfinder/userfiles/files/66616483910.pdfIn PDF document text
    • http://planet-for-events.de/userfiles/file/dolunabosopapuvofutopavan.pdfIn PDF document text
    • http://veoguidecostarica.com/ci/userfiles/files/51791515742.pdfIn PDF document text
    • https://fabriziochessa.it/userfiles/file/naxarajefijufanudepopax.pdfIn PDF document text
    • http://czyxchem.com/upload/files/lajofakumutifo.pdfIn PDF document text
    • https://www.osteopathe-montpellier-sud.fr/ckfinder/userfiles/files/torodozebamobogekepuged.pdfIn PDF document text
    • http://ambartakip.net/belgeler/file/zefakopekebiletidababe.pdfIn PDF document text
    • http://supair-lux.hu/ckfinder/userfiles/files/jalitosoga.pdfIn PDF document text
    • http://metamorfozyayincilik.com/userfiles/file/zodopap.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/161403c8743712---95207383055.pdfIn PDF document text
    • https://cukimentescukraszda.hu/files/files/90955289497.pdfIn PDF document text
    • http://tuzy.pl/Upload/file/45184440519.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=the+amazing+spider+man+2+download+on+androidPDF 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_off0000eeb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEB3 10968 bytes
SHA-256: 761208ab5ad229221a9e3a2251fa2c52aeb09a15f02c5a44de6f0b4a83e8c2bf
font_01_sfnt_off000107d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107D2 17708 bytes
SHA-256: 63bcc502ff34e3ec25c3e77c09ccf18a3aa2b85f0471a898befbabaada054b2d
font_02_sfnt_off00013606.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13606 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1