Malicious PDF — malware analysis report

Static analysis result for SHA-256 88a0e80c0c41d1bf…

MALICIOUS

PDF

80.6 KB Created: 2021-09-01 12:16:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: dd38cc888afe5c56c40358399b521446 SHA-1: 823322662e2381e5344d5f3a92297ea38d842e68 SHA-256: 88a0e80c0c41d1bfa6cae522ca40d5ed8e19e2a2581bc5ab6e68af4301dab1bd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised WordPress upload locations and other unknown domains, likely for phishing or malware distribution. No scripts were extracted, but the PDF structure itself is designed to host and present these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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 http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c92b9faba02---tuvisemug.pdf In PDF document text
    • http://thebankcardservices.com/uploads/files/9804492435.pdfIn PDF document text
    • https://gonguyenkhoi.vn/upload/files/vuwojufapulalomenawij.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16082ee97d06e1---77368298865.pdfIn PDF document text
    • http://www.annaleehuber.com/content_files/file/51010221883.pdfIn PDF document text
    • https://arerp.kr/data/file///79076735280.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608231679f4b0---7243689813.pdfIn PDF document text
    • http://worthingtonpark101.com/userimages/51395433310.pdfIn PDF document text
    • https://nikosdimos.gr/userfiles/file/gagurumotixebovebipixamas.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160ad986184355---1908084130.pdfIn PDF document text
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/5c738cc6ecd4c9df93d51162aa2e2053/77621364247.pdfIn PDF document text
    • https://tedesco.pl/userfiles/file/ledexolugoxu.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160d0b6b040803---zuposimuxalatukik.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160bd0722109e8---puxumu.pdfIn PDF document text
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160e132789753f---95912449457.pdfIn PDF document text
    • http://nappsa.org/userfiles/file/lenilanezakovojebizu.pdfIn PDF document text
    • http://slsnn.ru/content/file/xobaxewexamijukofax.pdfIn PDF document text
    • http://keitbg.com/images/files/bijimebubategovezaniseto.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a1d81d4a08---tebet.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/367f2a521c4230f52ec2e0616e08324c/negexuvix.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b1662d039fb---60153389005.pdfIn PDF document text
    • http://malbreil.com/userfiles/file/wewiri.pdfIn PDF document text
    • http://philippinesroadshow.com/wp-content/plugins/super-forms/uploads/php/files/126b8c29d5e2614667622bfa7620e3d5/63605381930.pdfIn PDF document text
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/dva7n8ur5s4rons1e7ahoukju1/xazufedimariwetizuxu.pdfIn PDF document text
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607c2d6452fdf---nulamezelevovesoram.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=culture+pom+puppyPDF 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_off0000d8e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8E3 10132 bytes
SHA-256: ad1839fb25b05acfe6def5d69f02b1b39d565cef37009eea5684933d764bc824
font_01_sfnt_off0000ef96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF96 17188 bytes
SHA-256: 3dbe685c5a64f65e5027b8ebfffe99e47167a34c3e758fb3e6c0a44fb2afdaae
font_02_sfnt_off00011bed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1