Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1250ff9358b76eb…

MALICIOUS

PDF

91.3 KB Created: 2021-07-02 15:51:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 61d489351d233a51dbe38d7c53222260 SHA-1: 7b05e68d11e27e49efa56751b58176ea757610be SHA-256: a1250ff9358b76eb20c21d08ac5bd798c1d219da3a5a2e071ed3cb0448009a1c
156 Risk Score

Malware Insights

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

The PDF contains numerous links to compromised WordPress sites, which in turn host other PDF files. This behavior is indicative of a link farm designed to distribute malicious content. The ClamAV detection and ML classifier further support its malicious nature, suggesting it's part of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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 http://www.everhouse.lt/wp-content/plugins/formcraft/file-upload/server/content/files/160a3f11ca17b5---wosonijiwutub.pdf In PDF document text
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/ebroaqt1f486vjhd71suauimj5/47051796332.pdfIn PDF document text
    • https://lawpropertyconsultants.co.uk/wp-content/plugins/super-forms/uploads/php/files/j0l0dd5j50gf7ra6fscms62h3u/17159088973.pdfIn PDF document text
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ac89d1ad884---gerupipevijuzeme.pdfIn PDF document text
    • http://s8radziejowice-paszkow.pl/userfiles/file/baporijawefuvuvalebu.pdfIn PDF document text
    • http://mariamozharova.ru/uploads/files/wunexabo.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160cadacdb490c---74380095156.pdfIn PDF document text
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/dmf3ltpr8dejkn4j4u464vq6bm/diwapokogivesazezagej.pdfIn PDF document text
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d57d22a790---1050679791.pdfIn PDF document text
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/160725149f2efa---tetuxoduwojage.pdfIn PDF document text
    • http://assessmentinsight.com/ckfinder/userfiles/files/gajaponereduvo.pdfIn PDF document text
    • http://ufnk.fr/app/webroot/files/file/53455252650.pdfIn PDF document text
    • https://traveltokiev.com/wp-content/plugins/super-forms/uploads/php/files/fetkuuc7ma2hjjv4i56pcp8sg7/papuvovolomiluwa.pdfIn PDF document text
    • http://www.consorcio.edu.pe/wp-content/plugins/formcraft/file-upload/server/content/files/16070c6324b68c---72094752286.pdfIn PDF document text
    • http://andlupa.com/userfiles/file/kodejimosivujuvanir.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086b025b5e7b---205474115.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb54888348f---vizukijosemuxoxusozij.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8cf5c4e184---serugowujumewu.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/9de459a0a80f5953cc070d74e8c6b995/62903866584.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/f8ef8c96dd3d0345a39ea183220fb962/lejizupar.pdfIn PDF document text
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/740f01a09b727d86aec45fb0d198bc10/46398920262.pdfIn PDF document text
    • http://summitremodelinginc.com/userfiles/files/75108961919.pdfIn PDF document text
    • https://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/c27530a41a2ff2396e05a91efe1199b2/koduvalipakadoto.pdfIn PDF document text
    • http://forumcutuca.com/ckfinder/userfiles/files/10249911526.pdfIn PDF document text
    • https://teenvolunteerhouston.com/wp-content/plugins/super-forms/uploads/php/files/f1cf6d80a190ca2133026740b81b0eb7/pepewibasabuz.pdfIn PDF document text
    • http://pressvaluation.net/userfiles/file/23987349971.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=vegetable+lo+meinPDF 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_off000100ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100CA 18264 bytes
SHA-256: 482aec4a761d75648238b680860c6dba356b6d11f6b2e33ab048016aa51056ff
font_01_sfnt_off000130e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130E1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000148f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x148F8 10292 bytes
SHA-256: 77ae01d958a77ad12cafa76e88035d607090fbb6b5af2a3cb58f23d26cc33a88