Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b2f7e6a4d9a419e…

MALICIOUS

PDF

74.0 KB Created: 2021-07-06 14:33:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 8875cd576e0f8a9807eb116052e5f843 SHA-1: 59448bc4d3c72afa77d954bbaf008b786c8ce593 SHA-256: 4b2f7e6a4d9a419e9222ee8d9e3362c45c9d0552ab1944ed80873f283492c934
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, containing numerous URLs pointing to disposable hosting and compromised CMS upload directories, likely to distribute further malicious content. The `wkhtmltopdf` authoring application suggests it may have been generated programmatically for this purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • 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 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://kvkumariajnkvv.org/singhania/downloads/file/81294929073.pdf In PDF document text
    • https://protechlighting.com/wp-content/plugins/super-forms/uploads/php/files/b807f63cdcddc54903052332fda6bc4c/gupareduxili.pdfIn PDF document text
    • http://www.magicapro.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a8bdcde197a---82204955231.pdfIn PDF document text
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afcbfe3185d---marurilogulosaneze.pdfIn PDF document text
    • https://tiklatakip.com/calisma2/files/uploads/76979291911.pdfIn PDF document text
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/16089cfe413b44---xamefasutiw.pdfIn PDF document text
    • http://reszke.pl/fckeditor/editor/filemanager/connectors/php/file/53594027719.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1607917f400d8b---lofubexifibux.pdfIn PDF document text
    • http://limitlessillusion.com/wp-content/plugins/super-forms/uploads/php/files/60eca1915495558dfbfdc9d0b315708d/sefukuwuwumitizij.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e9590789a4---51945560630.pdfIn PDF document text
    • https://premiersuli.hu/files/files/bolelodojas.pdfIn PDF document text
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16084077383f37---54192899520.pdfIn PDF document text
    • http://anonelectronics.com/admin/fckeditor/editor/filemanager/connectors/php/upload_jpg/file/202106020144406110.pdfIn PDF document text
    • http://macautemple.com/userfiles/file/womunajexig.pdfIn PDF document text
    • https://condominiovillage.com/userfiles/file/bogejur.pdfIn PDF document text
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/090dde3b32b1cd17259e3b940e6324f8/17672038259.pdfIn PDF document text
    • http://dgjst.com/upfile/file/foretubifetedalisi.pdfIn PDF document text
    • http://bellezaeimagen.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16070d4f88d2d1---93212608207.pdfIn PDF document text
    • https://muguet.fr/sites/default/files/file/63328945297.pdfIn PDF document text
    • https://daleplumbinginc.com/wp-content/plugins/super-forms/uploads/php/files/5c4fc84d258e215c7685d6f6e1ee1aae/peneninowezejov.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dbb02d9da84---ritulenezi.pdfIn PDF document text
    • https://mymango.ru/wp-content/plugins/super-forms/uploads/php/files/0f2008ee03d2411d903a74a1ec2f054d/lutezagatudef.pdfIn PDF document text
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c301cef1ecf---medozo.pdfIn PDF document text
    • http://chupanhnoithat.vn/upload/files/gizebubilifuz.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608059e813ce0---90048486784.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=new+hollywood+movies+2020+tamil+dubbedPDF 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_off0000bc16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC16 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d428.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD428 17020 bytes
SHA-256: e2339ee062e3ac676a083e4e72342267a12eb8d76466037dd9d5bbed3a2fbb18
font_02_sfnt_off000100b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100B5 11036 bytes
SHA-256: 39e4fe11fca3c220fda3d90d1c95032f1ca2844fcfc043492179b82c2341d3ca