Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4b43b5dc7b204d6…

MALICIOUS

PDF

87.9 KB Created: 2021-07-05 20:59:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: add0f4322641237c34a4fd25d0e82b87 SHA-1: 95f43df8e6ad7d3de23956cf40eaf777127f6da9 SHA-256: b4b43b5dc7b204d6a48673eec3104008c967bd316868e4f6b98a8ba352512b54
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains embedded JavaScript and a large number of external URIs, many of which point to compromised websites or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document is a non-clustered link farm, suggesting its primary purpose is to redirect users to other sites, likely for malicious SEO or phishing campaigns. The embedded JavaScript further supports malicious intent, potentially used to exploit vulnerabilities or initiate further downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://krisoc.ru/uplcv?utm_term=heat+of+the+night+guest+stars PDF link annotation
    • http://bbpcosmetics.com/admin/upFiles/2021-5/file/43872924.pdfIn PDF document text
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160859a096111f---60867309516.pdfIn PDF document text
    • https://deltarents.com/upload/ckfinder/files/33188208866.pdfIn PDF document text
    • http://cameralehiep.com/hinhanh_fckeditor/file/84218690152.pdfIn PDF document text
    • https://southtours.com/wp-content/plugins/super-forms/uploads/php/files/me2u8j07viemlsr95vokqddia5/26796642655.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cebc3a2bba3---4763902854.pdfIn PDF document text
    • http://kondicionery-dolgoprudny.ru/upload_picture/file/9185047728.pdfIn PDF document text
    • https://ancoraeducacion.com/images/24133705411.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/7fe29d6a40b9c4409694e060e002a8d2/73863344749.pdfIn PDF document text
    • http://www.bash.cl/media/file/55309068299.pdfIn PDF document text
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/c5ca6b5b631404a11cdd8156048a076a/xekivavexen.pdfIn PDF document text
    • https://sckprime.com/wp-content/plugins/super-forms/uploads/php/files/758b18f58cb944cc745d4824b8bc0e2b/wupuxone.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/hsl6oo6c1vo28p9i6o1sq2rj9c/45613553831.pdfIn PDF document text
    • http://www.retorika-zidar.si/ckfinder/ckeditor_uploaded_files/files/kidusibipifetakanev.pdfIn PDF document text
    • https://www.abaco-engineering.it/wp-content/plugins/formcraft/file-upload/server/content/files/160cb05738718d---rimerore.pdfIn PDF document text
    • https://www.drmarlenebothma.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160be44ccacb42---fopanilumixi.pdfIn PDF document text
    • https://nguyenhungstone.com/uploads/image/files/60449016816.pdfIn PDF document text
    • http://varanini.pl/userfiles/file/puzumodeburitenaseg.pdfIn PDF document text
    • http://newdimension.su/userfiles/file/zotegotem.pdfIn PDF document text
    • https://www.prestigeautobody.com.au/wp-content/plugins/super-forms/uploads/php/files/ffa7fa814bc158a8e15442c215f7442c/jozapinenavukisolizi.pdfIn PDF document text
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/6df8a284ae42f3c39e0a1980ffc31802/93790148356.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/npsaco11hv955bmfh24u6p9p64/xonukenabutut.pdfIn PDF document text
    • https://careersourceokaloosawalton.com/files/public/18539578124.pdfIn PDF document text
    • http://cuborh.com/natelinhanew/js/ckfinder/userfiles/files/76238983635.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/pndtmmn657f5hr2618spls6euv/pikejawunalefosanimo.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_off0000f211.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF211 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010a28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A28 10536 bytes
SHA-256: 485c01d7d2c1ff9e02deb2635a39bb57e656f0b4f89c934b3dd62389347b69d8
font_02_sfnt_off00012214.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12214 17868 bytes
SHA-256: de45136d13e6bdd4b9687d94aee6e311d8303a0c79d5714c24a92fce1290080a