Malicious PDF — malware analysis report

Static analysis result for SHA-256 a0c66f7035d899f0…

MALICIOUS

PDF

72.6 KB Created: 2021-09-01 20:16:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 55e21a867a1b752b19b4fc044100ff49 SHA-1: 6ec3a9a3c35afec6f42aadcf5c1dd1958c632d4a SHA-256: a0c66f7035d899f02ebbd4d4bc4fcf2c14adf57edb77d49f1e5bbca55c3725a2
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites or other disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a deliberate structure designed to host many links on various domains. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://cructi.ru/uplcv?utm_term=how+to+say+myself+in+an+interview PDF link annotation
    • https://contabil-fiscal.ro/mm/file/38338306279.pdfIn PDF document text
    • http://bastola.org/userfiles/file/91973658373.pdfIn PDF document text
    • http://beulahcooleycollection.com/clients/870349/File/morurolamiburirikenizupix.pdfIn PDF document text
    • https://bowenpainter.com/wp-content/plugins/formcraft/file-upload/server/content/files/160798139acf99---gavusix.pdfIn PDF document text
    • http://sun-green.eu/ckfinder/userfiles/files/2717166775.pdfIn PDF document text
    • http://wdnederland.nl/file/pajawuwerunekanej.pdfIn PDF document text
    • https://purebodycare.courses/wp-content/plugins/super-forms/uploads/php/files/ca34ftbbh62n03u5966g0h6jcs/vozusazipesesinovape.pdfIn PDF document text
    • http://rotarylaspalmas.org/documentos/file/97949878105.pdfIn PDF document text
    • https://pinkrali.com/calisma2/files/uploads/nivawezajad.pdfIn PDF document text
    • http://www.orarestauratorisaf.it/wp-content/plugins/formcraft/file-upload/server/content/files/16097b3eec79fc---sugiwudirafu.pdfIn PDF document text
    • https://china-glass-mosaic.com/userfiles/files/20210604_062706.pdfIn PDF document text
    • https://investmentskillsgroup.com/images/userfiles/file/levopixenizamapimumusa.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/102bbd8e5dc5f75e9500ef3bf3105205/xowizezuzapasowovulofeb.pdfIn PDF document text
    • http://15thstpresbyterian.org/clients/d/d7/d7025cfb1d4df99eee5a588ecc3dd57f/File/65801933578.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/1609bbc48c50de---58526106438.pdfIn PDF document text
    • http://decamiones.com/userfiles/file/kuvesogo.pdfIn PDF document text
    • https://emauto.lv/index/images/up/file/88590004233.pdfIn PDF document text
    • http://capitalclassof1970.com/clients/e/e7/e78cae7b17622b0161c193cbd63f4fd0/File/denojefovovosivojemoluj.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_off0000b9c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9C1 16840 bytes
SHA-256: 25353c10d9fdd9afa5c948cdc65dd2858072a4f28a1d485416349128d575ef9b
font_01_sfnt_off0000e4dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4DD 10632 bytes
SHA-256: fc6d89db307a096d5b75e9a082e260fab6de60fce2b310c28e48dfb714b830a8
font_02_sfnt_off0000fd34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD34 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1