Malicious PDF — malware analysis report

Static analysis result for SHA-256 377bb699b998bc8f…

MALICIOUS

PDF

101.3 KB Created: 2021-06-29 11:11:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: a1fe1074974cea569c873f1458fe4088 SHA-1: 6dc34acc483fd4f7da2e33cea91c367c040df4c9 SHA-256: 377bb699b998bc8f467c9b7841b31fa173ea7732059f95a6310541379b398200
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. It contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm or phishing lure. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' reinforces this assessment. The primary goal appears to be redirecting users to potentially harmful external content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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://queure.ru/uplcv?utm_term=he+that+believeth+and+is+baptized+shall+be+saved PDF link annotation
    • https://acryl-bg.com/userfiles/file/97875757380.pdfIn PDF document text
    • http://cichanski.com/Upload/file/ronilivawakuk.pdfIn PDF document text
    • https://bostoncake888.com/UserFiles/files/47998822276.pdfIn PDF document text
    • http://glamour-nsk.ru/ckfinder/userfiles/files/xuvomilisojagolulanegufob.pdfIn PDF document text
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160912e6354189---62484781041.pdfIn PDF document text
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16081821fa8855---lenaxokonakawufor.pdfIn PDF document text
    • http://vorne-sitzen.eu/pcms/content/file/bozovezifajotane.pdfIn PDF document text
    • https://maribon.net/app/webroot/files/userfiles/files/27619546442.pdfIn PDF document text
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/16077a73246519---81106156317.pdfIn PDF document text
    • https://atamergranit.com/userfiles/file/49937919070.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609c77596f2a1---6557208795.pdfIn PDF document text
    • https://bwawarszawa.pl/upload/file/70374853577.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606eab9c70cb3---mexazudisirakotin.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608be3e0dd039---gisuvesoza.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aca34bef982---47559800851.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095db5fd0d75---wexuxubiguluvibexeka.pdfIn PDF document text
    • http://teplospectr.ru/images/files/risojasukoxeruxufepo.pdfIn PDF document text
    • https://expresstestingatl.com/wp-content/plugins/super-forms/uploads/php/files/a6edb7e6e4e4aea879f0c10e7b7b16d2/fezabunasowovadited.pdfIn PDF document text
    • http://t-eamplus.de/web/editor/files/jubufugapege.pdfIn PDF document text
    • https://apparel.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/5b0e6e98e1b5f6a89354eb38ff89047f/77861144693.pdfIn PDF document text
    • http://rolfingnaples.com/clients/a/a5/a5422f62036d2d393d866963e902351c/File/tuparoxow.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b097b062c27---loxagegokafojiwati.pdfIn PDF document text
    • http://antwerp-reefer-tournament.be/argt/files/budizo.pdfIn PDF document text
    • https://jollytime.ru/wp-content/plugins/super-forms/uploads/php/files/d1967729d7fe8b7f719fb75f132fabea/rekibelakubazotet.pdfIn PDF document text
    • 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_off00012cca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CCA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000144dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x144DC 16756 bytes
SHA-256: 3b33cdd5e285e8d1396b6e938207b20ba695e2c67aa348a95c32e68a2a99ae60
font_02_sfnt_off00017000.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17000 10528 bytes
SHA-256: d1d3f97429dd20cdb14f1a4530a9e0156284b9643d9885e1f7fd8bd6519c4ca0