Malicious PDF — malware analysis report

Static analysis result for SHA-256 05c89b5728ffa3ba…

MALICIOUS

PDF

103.1 KB Created: 2021-09-06 23:55:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 98ebd723a4cde02efe59e2c164a05df6 SHA-1: 3074b3403bcf05d51e53efc536345d539ad16bc7 SHA-256: 05c89b5728ffa3ba91ded5dbd9b06ae7df9655daa4d8284926634f84d45c574c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple compromised websites hosted on disposable infrastructure. The presence of numerous unknown URLs suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9926

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 https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16098302551bcc---34156947354.pdf In PDF document text
    • http://beachfirebrands.com/userfiles/file/zarusunonujozolepozipa.pdfIn PDF document text
    • https://dienlanhhonganh.com/images/pic/file/pokuwovadituwikiweresibu.pdfIn PDF document text
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607a545596b6d---95621173696.pdfIn PDF document text
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/vixapezepoxosifofobolasig.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160adce29dc9c3---pizavixewulimipumu.pdfIn PDF document text
    • http://gonvvama.net/filespath/files/20210816190633.pdfIn PDF document text
    • https://carcarnet.com/home/sandbox/domains/hkdance.tritek.hk/public_html/ckfinder/userfiles/files/rarisepitan.pdfIn PDF document text
    • http://fteq.ru/files/file/tikazunofunamufenoluv.pdfIn PDF document text
    • http://ejmk.com/ej/upload/files/34838972866.pdfIn PDF document text
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160856747abe47---nazatedigi.pdfIn PDF document text
    • http://branpc.in/ckfinder/userfiles/files/64189909380.pdfIn PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/co54ejkv33vv268ds648sm4416/pegazebuvumesemozora.pdfIn PDF document text
    • https://actioncoach.com.my/wp-content/plugins/formcraft/file-upload/server/content/files/160aaac8d4d9d9---43812472119.pdfIn PDF document text
    • http://perrymanreunion.com/clients/f/f8/f8644f0eb9578147d5589f75b8c3e300/File/87522237388.pdfIn PDF document text
    • http://teaandtiarasottawa.com/clients/e/e8/e8f54e69a7463df9fd0adff13cd8e90f/File/gidibopusisubasuxa.pdfIn PDF document text
    • https://allianztc.ro/files/file/53711874465.pdfIn PDF document text
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607cb0ff24211---53706150869.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/16111940f2e494---35696212405.pdfIn PDF document text
    • http://campingwithconvenience.com/files/files/gezef.pdfIn PDF document text
    • http://www.northern-japan.com/image/upload/File/75077566713.pdfIn PDF document text
    • http://motivationandmomentum.net/ci/userfiles/files/93047263415.pdfIn PDF document text
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1a2dc18796---gifudebisesonebu.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/7illeq9ga3bh991jalikbho826/55970796433.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=elevate+science+grade+4+pdfPDF 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_off00012d6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D6A 10804 bytes
SHA-256: 391cf760ad5698ec66362ea8456440c77a035024a57a4ecc024085f9b7f504fe
font_01_sfnt_off00014637.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14637 19036 bytes
SHA-256: d5ff19756b9a27f8b18223ad3dda7724f006300ef0ab697e9fc4b94f3799dcaa
font_02_sfnt_off00017710.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17710 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1