Malicious PDF — malware analysis report

Static analysis result for SHA-256 d13c61ee45f7d70c…

MALICIOUS

PDF

75.3 KB Created: 2021-09-03 02:52:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 1f49a33cb5a9b8cdd2520401e478502a SHA-1: 07dae917c8425ae21a2ab80a1f97862efe4eb0d9 SHA-256: d13c61ee45f7d70cfee0145f6583d540ed6ed4af5db754cb42e3f6b2fb6a2d29
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress sites, which in turn host other PDFs. This suggests a link farm designed to distribute malicious content or lead users to phishing sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery via a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/2e55oav52dvtogkqoh5ou1q81p/bajebapav.pdf In PDF document text
    • https://grand-forge.ru/wp-content/plugins/super-forms/uploads/php/files/02179e7a20a22065f30a4fa3efd1c38f/97739111283.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ae2ecda4fbb---wiwutavibisarupat.pdfIn PDF document text
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/160745489597ce---67896824262.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609dc4db0f204---xuwifidexe.pdfIn PDF document text
    • http://broadgatecapital.com/userfiles/file/vugitezije.pdfIn PDF document text
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/3be3cea3b37252781b9828004ed39ff0/6165512282.pdfIn PDF document text
    • http://ablerexthailand.com/userfiles/files/61271697056.pdfIn PDF document text
    • http://goteneplast.se/files/images/file/mebavawowowul.pdfIn PDF document text
    • https://jollytime.ru/wp-content/plugins/super-forms/uploads/php/files/65f9caf61f091a2bc0794fb96748450e/vusonibiwanux.pdfIn PDF document text
    • https://lightspec.com/wp-content/plugins/super-forms/uploads/php/files/f21600cdf40c7c40db4430b6e056589a/65354180205.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/5p96u0lu36a44iq8d6tvbtisa1/94001914686.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608a1c3fc2d81---41626854742.pdfIn PDF document text
    • https://law.com.sg/wp-content/plugins/super-forms/uploads/php/files/3abc3ef50b5700f937dc84abcd4040cc/30099878344.pdfIn PDF document text
    • https://samsunyapi.com/userfiles/files/nurunubunase.pdfIn PDF document text
    • https://msr-hudsonproperties.com/wp-content/plugins/super-forms/uploads/php/files/494fdb6564dba18383521f85059a1e4c/megibebefisuz.pdfIn PDF document text
    • https://www.waterlooarmsnewforest.co.uk/wp-content/plugins/super-forms/uploads/php/files/aefbb108478b0606468e48a40c651b32/zavopuminofozisat.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160737ccc0c9e6---15315882442.pdfIn PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070928f39b33---soguzo.pdfIn PDF document text
    • https://777mto.com/contents//files/mevamibezam.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/ccpfsq8b4cosdk8tncpeb530r5/47895743770.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc23188ad34---59352313207.pdfIn PDF document text
    • http://www.aportecnica.com/imagenes/editor/file/sanokipasumavezotifigop.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=symbolic+logic+by+copi+pdfPDF link annotation
    • https://www.rt9.rspo.org/ckfinder/userfiles/files/vadotenesafulazubix.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_off0000c353.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC353 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000db6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB6A 10528 bytes
SHA-256: 866a76ae7ed289fdc0a16b622407c4c0a7ad8aa87c41b7b76ded45b4eed0e6ca
font_02_sfnt_off0000f2ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2EE 17408 bytes
SHA-256: bf1becf656bccb5817e8cb8136c621b6e76836ea5bda5fd48c3c412b4e6173d1