Malicious PDF — malware analysis report

Static analysis result for SHA-256 6e21dbfb55a0371b…

MALICIOUS

PDF

87.8 KB Created: 2021-07-01 10:25:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f0b6abc2dc6293a4457df5f9436f8fac SHA-1: aa03422259c8dacda230eb6509d16332ab826399 SHA-256: 6e21dbfb55a0371b2324cea469f141bfb5180700ffaef0ad217206bb7c2d49c5
96 Risk Score

Malware Insights

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

The PDF file contains a link farm with 25 distinct hosts, many pointing to compromised WordPress upload storage. The ML classifier strongly flagged this PDF as malicious. The primary attack pattern involves directing users to potentially malicious or SEO-manipulated content via numerous external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 5

  • 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 http://ztkammer.at/uploads/file/97701846660.pdf
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/73i8kd0jkfj5lkovej4ovto34l/8170737487.pdf
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/2ff6c52b05b221d712f04d0ab521daa5/kesorizarifojopejas.pdf
    • http://sixtyguildersresearch.com/admin/photos/file/77964587273.pdf
    • http://greenld.com/userfiles/45581789550.pdf
    • http://haustechnik-hagenauer.at/15823795906.pdf
    • https://paloaltospeakerseries.com/wp-content/plugins/super-forms/uploads/php/files/2a10d1c87391d50cb9584a522c59dbbb/gikuriwukadunegejo.pdf
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b29eb84ee4---vofufexomuwesujudanit.pdf
    • http://bazatalty.pl/wp-content/plugins/super-forms/uploads/php/files/4bf5bcd10ba79d1da1728338b5216232/88516219656.pdf
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c3596728be---31652022555.pdf
    • https://regeneracion-capilar.com/wp-content/plugins/super-forms/uploads/php/files/245ec84225ee452dfda5f5f1ee9d3134/pidujogi.pdf
    • http://seamacros.com/upload/file/52114110992.pdf
    • http://saamfactory.com/wp-content/plugins/super-forms/uploads/php/files/79117990d5d2d52b21f2e75e10f12387/76471981417.pdf
    • http://yjsyrj.com/userfiles/file/36883348798.pdf
    • http://ketoanantamhcm.com/uploads/files/jefevujanivusupo.pdf
    • https://www.beewellrx.com/wp-content/plugins/super-forms/uploads/php/files/tmp/fevikexig.pdf
    • https://frontiersneurophotonics.org/wp-content/plugins/formcraft/file-upload/server/content/files/1/160bb72c68df04---22751436653.pdf
    • https://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a94f7a50b13---zafomiso.pdf
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/34a98e8dd7bc7f2a372accadfd21c984/87655999889.pdf
    • https://sunarchegypt.com/userfiles/file/rirefoxiranodapikuxoz.pdf
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/160919a9b548fd---25968325334.pdf
    • http://dajuicebarus.com/uploads/files/22778790552.pdf
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1606c73be83198---60120725623.pdf
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606cd35d991c2---witovodijixobopef.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb155167b9---20875439119.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=communion+with+god+bible+verses
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f51d.bin
0869aeecc4bb21a9e42e6019647da6121d01ed984f432c83fcec14aef53abd42
pdf-font-stream PDF embedded font (sfnt) at offset 0xF51D 16868 bytes
font_01_sfnt_off000120dd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x120DD 16792 bytes
font_02_sfnt_off000138f4.bin
6c76acc16b2edcf7eae0690f981e9d0e389d9e8871013963fab392a08e3be64e
pdf-font-stream PDF embedded font (sfnt) at offset 0x138F4 10956 bytes