Malicious PDF — malware analysis report

Static analysis result for SHA-256 c800378a11e297b3…

MALICIOUS

PDF

79.7 KB Created: 2021-09-16 20:31:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 3a3e773a0737a990884bb24a47eff401 SHA-1: f79c31e406aa4382ba02288f5c6c3e759cf6eb54 SHA-256: c800378a11e297b3869b497706ac1c8a6657802726eae76f4c98e86fe37fc9ce
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection for 'Pdf.Phishing.Trojan' and an ML classifier indicating maliciousness. The heuristics 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' indicate the document contains a farm of links pointing to potentially compromised or disposable hosting, designed to redirect users. The presence of numerous unknown URLs further supports this, suggesting a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://prefinancovaniehypoteky.sk/res/file/44882983222.pdf In PDF document text
    • http://yuha.be/_files/file/pukejuwitenirodul.pdfIn PDF document text
    • https://www.ijestr.com/ckfinder/userfiles/files/29952181618.pdfIn PDF document text
    • https://vandolderskb.com/images/usr/dotometafekejekebilubif.pdfIn PDF document text
    • https://imihwa.com/uploads/image/20210912/files/20210912040218.pdfIn PDF document text
    • http://koyomisushi.com/uploads/files/1582607958.pdfIn PDF document text
    • http://analhospital.net/file/files/48034884261.pdfIn PDF document text
    • http://xlsferrosilicon.com/d/files/73516186004.pdfIn PDF document text
    • https://www.borzabadi.com/ckfinder/userfiles/files/7703953370.pdfIn PDF document text
    • https://praktijkbinnenstad.nl/file/zirofawudi.pdfIn PDF document text
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/de61fcc897e33cffb30d6d18abd424dd/27955394558.pdfIn PDF document text
    • http://musicpark-live.de/userfiles/file/judadowananadidalolo.pdfIn PDF document text
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/16133db96daeac---ledajejitenakek.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/pkkhoavp8qqej9vb4ot5gh3dp4/relurarinudofobotadiguk.pdfIn PDF document text
    • https://tpk-m.ru/files/file/5466394844.pdfIn PDF document text
    • http://twfbs.com/ckfinder/userfiles/files/mitelidixezesupelar.pdfIn PDF document text
    • http://metabolitplus.ru/files/file/kajutemuwiraku.pdfIn PDF document text
    • https://abcoegypt.com/userfiles/files/netuboniwuxa.pdfIn PDF document text
    • https://bibliothequedesarts.ch/ckfinder/userfiles/files/dovodis.pdfIn PDF document text
    • https://bio-obst-und-gemuese.de/userfiles/file/44358249274.pdfIn PDF document text
    • http://digitalpolicycouncil.org/imagenes/file/62707454440.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/243bp5kb99aqukcs8i6hvuvo09/46916467173.pdfIn PDF document text
    • http://kommunikator.nu/demo/userfiles/file///buwemew.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=lire+un+pdf+sur+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_off0000d287.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD287 18972 bytes
SHA-256: ba8181d4d26307aef67b02fc891203a837f6dd370b0253e9bfbdffe38bcd394b
font_01_sfnt_off0001022c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1022C 10404 bytes
SHA-256: 115815192de21c4b9b029a7a17a4cd5473731f1ab7a66a37ecbde2e803878bca
font_02_sfnt_off000119d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119D2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1