Malicious PDF — malware analysis report

Static analysis result for SHA-256 88ded0cf67b25019…

MALICIOUS

PDF

87.5 KB Created: 2021-06-25 18:18:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 25ceb433816a59241722938eba749c47 SHA-1: 1b848973fdac33b246dffc45c0ae0ac2917730a3 SHA-256: 88ded0cf67b2501985cbc4caeb7d0e91292a2383b324ebf9b66a439ab302c44f
196 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and ML classifiers. It contains numerous links pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The presence of multiple PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/1606e113965015---73026666242.pdf In PDF document text
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/719933f2c00782906ee81193ee75f394/kovofaposodusoj.pdfIn PDF document text
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be4ea882981---99576120904.pdfIn PDF document text
    • https://opuntia.eu/wp-content/plugins/super-forms/uploads/php/files/1d000d7354731516ba9f14f14f32436d/38389065698.pdfIn PDF document text
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/160b87a921d9e5---katavukemubanunakoj.pdfIn PDF document text
    • http://nordicaluminium.ru/userfiles/file/sidifutewifukaxa.pdfIn PDF document text
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160ab3d17edf5a---33998459623.pdfIn PDF document text
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/b050cc3a86741f963ba4f95ccc33b558/78092606175.pdfIn PDF document text
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/sivetpv15ei84njrhelh1bk8od/zefatajuludafoxiwar.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160727a64d6cd7---lonojapafizetejerafa.pdfIn PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/8329apjf2e9kq9s643612k7hrf/gizobadapo.pdfIn PDF document text
    • http://xn--80aaae7amexjfdlfdfg.xn--p1ai/files/file/xasufudirofowili.pdfIn PDF document text
    • https://xn--64-mlcufjjaii0l.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/a7a335a2929c200f14cf71c70c7eff22/batetafozegiv.pdfIn PDF document text
    • https://ocvirapuato.com.mx/wp-content/plugins/super-forms/uploads/php/files/068e074edc31bd0d83099db04be88ccf/57701300179.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c593f7cee7e---fojibogijoluzamoxelul.pdfIn PDF document text
    • http://jointrilogy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c65c16337c---wirixujorijudotu.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d91393bfae---10290241857.pdfIn PDF document text
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/8809646e85e7da93426b9760ac9cc5de/87303506851.pdfIn PDF document text
    • https://dichvuketoanvn.org/uploads/files/lipiselebo.pdfIn PDF document text
    • http://www.canadavisaservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d6d051c172---zoxulex.pdfIn PDF document text
    • https://lea-inc.com/wp-content/plugins/super-forms/uploads/php/files/4ca874b24bfd33e340a1a26115dd1924/sapagoxixupe.pdfIn PDF document text
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a74d427e783---mafitipemola.pdfIn PDF document text
    • https://ambulatorioveterinariosismondi.eu/file/putivuzisadefikinudowuna.pdfIn PDF document text
    • http://drukarnia-skawina.pl/app/webroot/media/files/10228591084.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/f5c52a3e62475b7f3993c7472da48d5d/26266335072.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a624899d8ec---nifafofanikutusuj.pdfIn PDF document text
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/07pa777rf3rlc6etlm1hb5s840/pebulebomo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=love+life+meaningPDF 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_off0000f4df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4DF 10212 bytes
SHA-256: 1cd7134563a2599fdfe7d3363a1742f30f98d5f39545d8d399106e9043ffa938
font_01_sfnt_off00010bb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BB3 17116 bytes
SHA-256: 9c8d7023f9a464f0601e2d4adb49d2362d74eace52bd5623b60b035929037359
font_02_sfnt_off00013858.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13858 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1