Malicious PDF — malware analysis report

Static analysis result for SHA-256 6435b49f869af244…

MALICIOUS

PDF

82.8 KB Created: 2021-09-02 08:49:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: f4198dfe6ddc02ef22ef3fbe5a64ab7b SHA-1: 76bbbb9196976bdb13c9e257a1cc85decc5d3d96 SHA-256: 6435b49f869af244b22d8d754f77288a72005164589dfa4a2a3c41e42329ae23
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://infrive.ru/uplcv?utm_term=what+does+tps+stand+for PDF link annotation
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/7b8dfc84dbf6029ef045eda4735b0239/latisemetigobuwop.pdfIn PDF document text
    • https://fwullong.com/upfiles/editor/files/lerumurovalixoriwu.pdfIn PDF document text
    • http://booklandbooks.com/userfiles/file/pazulasarilupunin.pdfIn PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/9d76b6da2a19261135702625ab520502/51760761691.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160e4a5514c5c3---6443916440.pdfIn PDF document text
    • https://hophamthaibinh.com/upload/files/82242272371.pdfIn PDF document text
    • http://kantoromega.pl/userfiles/file/29465931968.pdfIn PDF document text
    • http://murielbellhomes.com/userfiles/files/lirurawidusesewe.pdfIn PDF document text
    • http://musorcentrum.hu/files/article/file/wakap.pdfIn PDF document text
    • https://centrobrands.com/wp-content/plugins/super-forms/uploads/php/files/281996721ba079562c642587381fbd8c/96516160322.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160761618682da---4720775882.pdfIn PDF document text
    • https://biographiewerkstatt-singer.de/userfiles/file/wumire.pdfIn PDF document text
    • https://digireg.si/upload/sasukefewesetatabenenat.pdfIn PDF document text
    • https://volgogradexpo.ru/ckfinder/userfiles/files/86672494747.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609ee72857269---demuvufijape.pdfIn PDF document text
    • https://hazeloyun.com/calisma2/files/uploads/60289861523.pdfIn PDF document text
    • http://medicapoland.pl/uploaded/file/96365428794.pdfIn PDF document text
    • https://mmoxx.mn/userfiles/files/lexizinugif.pdfIn PDF document text
    • https://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/37hvqnc33uc863oq38g1l2p6lq/79214163388.pdfIn PDF document text
    • https://kar360.com/resimler/files/jojokivi.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160944f3ca0b43---ginojotobakudilogawel.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_off0000de36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE36 18100 bytes
SHA-256: 925e467682eb60f8948bae1c477a5869bad11944067176851dbd2914ea48ba70
font_01_sfnt_off00010d61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D61 10452 bytes
SHA-256: b31d37b7e99ddbebe98de3d6cd3443db3fdc2b1f4d77b138c998f2c0199cd304
font_02_sfnt_off00012512.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12512 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1