Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5c4ceb665f345e3…

MALICIOUS

PDF

78.3 KB Created: 2021-09-08 09:56:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: f495566f98e12ee6e825748fbadc1a35 SHA-1: c2e6daf72591928a3a07ffb272e1bb2286bfb130 SHA-256: b5c4ceb665f345e369bb088190fb2eccf23ab1886b9a657aceddbf6c706319ba
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous external URLs, many of which point to other PDF files hosted on compromised websites. This structure is indicative of a phishing or malware distribution campaign, aiming to lure users to malicious content. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://graffitipaintstudio.com/wp-content/plugins/super-forms/uploads/php/files/5bfee6f9cd050ae06330a5545bb47391/fenonafakapabivegedanutuf.pdf In PDF document text
    • https://nhahangthanghuong.com/uploads/files/35371797297.pdfIn PDF document text
    • https://vanvoorst.info/uploaded/file/81290418326.pdfIn PDF document text
    • https://reklama71.ru/upload_picture/katevokaw.pdfIn PDF document text
    • http://alimentosldm.com/userfiles/file/80163909495.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087246f08984---miwunit.pdfIn PDF document text
    • https://www.reachcast.ca/wp-content/plugins/super-forms/uploads/php/files/8473ac26dd0b29438e4d1ca55329855d/kilugejewizepitok.pdfIn PDF document text
    • http://quesnelbusinessnetwork.ca/userfiles/file/vajukemososogox.pdfIn PDF document text
    • https://harryfok.com/ckfinder/userfiles/files/rerezozawerafegeli.pdfIn PDF document text
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bbc903cb40---novizazejel.pdfIn PDF document text
    • http://www.victoriousintl.com/new/resource/files/jikuwipatude.pdfIn PDF document text
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/1607212b87f94b---82832006669.pdfIn PDF document text
    • https://genegurumiraclehealer.com/userfiles/file/lotapajuzikudodojukefowe.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/915a1e9b3a290cd87ac38546ac2cba0c/pimofedupu.pdfIn PDF document text
    • https://syntellect.ru/Repository/file/20397706585.pdfIn PDF document text
    • http://babyindex.nl/images/uploads/tabaruweferevukifobejonis.pdfIn PDF document text
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609273dad1e28---rojakupofusubavatis.pdfIn PDF document text
    • https://hamzsabegi60szallo.hu/UserFiles/File/27230087432.pdfIn PDF document text
    • http://dolonchem.com/upload/files/fidotevekofoj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=pencil+drawing+books+pdf+downloadPDF 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_off0000cf9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF9A 16856 bytes
SHA-256: 69241476377cd6f5dc179129fda082fd653d6d402aca6487716a2f1bdd0732c5
font_01_sfnt_off0000fad4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAD4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000112eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112EB 11016 bytes
SHA-256: a037175f2d043ec3b2c300ecfe5f9b9e6d6eda602915fcc0e0eff946b041e1c0