Malicious PDF — malware analysis report

Static analysis result for SHA-256 43a0ad982dfb1b2e…

MALICIOUS

PDF

96.5 KB Created: 2021-07-07 08:02:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 390b5cd293566e2634b947460fcfee11 SHA-1: 59c30e1c3a2b57ab41b3141955440efeea0afedb SHA-256: 43a0ad982dfb1b2e06ff210bee1526de5b124552a16ace58e47763f897588fb5
216 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a high number of links pointing to compromised WordPress upload directories and other disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely to deliver a second-stage payload. No scripts were extracted, but the PDF structure itself is indicative of a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

Heuristics 8

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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://mehreganimaging.ir/images/upload/files/82182685624.pdf In PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609c301e092b4---8282573703.pdfIn PDF document text
    • https://dhesient.com/media/18715904567.pdfIn PDF document text
    • https://jclifeschools.org/wp-content/plugins/super-forms/uploads/php/files/1b3339c9ae00fa0830701b620585cc6f/7078782852.pdfIn PDF document text
    • https://www.travelticket.com.au/wp-content/plugins/super-forms/uploads/php/files/hg82005ep8qom95ugg367jgjsr/bexozuxanesekikurijufopi.pdfIn PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/9d6ksmg3or90aq4o6ad1mqqss3/96863100349.pdfIn PDF document text
    • http://bhs76reunion.com/clients/e/e7/e717e6e8e39ea4daeda922698d41f3c9/File/ferisonivaruxagusilefam.pdfIn PDF document text
    • http://highlandhighclassof1962.com/clients/c/c3/c330a44b04b080977bf299ea430a317d/File/26737440688.pdfIn PDF document text
    • http://nccutrackandfieldnation.com/clients/2/2c/2cea5a7e730406ee40dfbbde6098010c/File/razivepufim.pdfIn PDF document text
    • http://abpaluso.com/upload/file/wikubamesimibafiralexuf.pdfIn PDF document text
    • https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/b333691a6ebb8d58d4bab53ee715078a/28817963271.pdfIn PDF document text
    • https://outsourcedbackoffice.co.uk/wp-content/plugins/super-forms/uploads/php/files/e7de225a3583163d71441730d2450647/lekusosakulizedopevuwago.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609ab60d3ff5e---jozugerotapiliwarezisoku.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/mgmqhduv6bcr9ak51cnutmrpa4/34064305961.pdfIn PDF document text
    • https://www.myjamaicais.com/wp-content/plugins/super-forms/uploads/php/files/1ad2863438a73e08f538f03072c0b75a/47604245615.pdfIn PDF document text
    • http://willettelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/vinogotoxegavorito.pdfIn PDF document text
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/0de9169279622891aa5828a446be5cbe/kewerivopotewi.pdfIn PDF document text
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/16083f39022624---50833205047.pdfIn PDF document text
    • http://ambulatorioveterinariopisillibertozzi.eu/userfiles/files/safedowet.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4b661a0fcb---98959548574.pdfIn PDF document text
    • http://stolizstekla.ru/userfiles/file/55643214245.pdfIn PDF document text
    • http://zge-led.com/luodan/images/userfiles/file/66253062381.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160947c674fd51---5774421398.pdfIn PDF document text
    • http://22743333.com/userfiles/files/13018293347.pdfIn PDF document text
    • http://unnatiwelfareorganization.com/ckfinder/userfiles/files/50936014605.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=d+and+d+sheet+pdfPDF 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_off0001173d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1173D 10240 bytes
SHA-256: 35b6ca1a3ec119bbe4a314c76ed7c9ac2713bfc4a3efbe888e3cb9dc2f16d2ce
font_01_sfnt_off00012e2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E2B 17648 bytes
SHA-256: 7bdfa0ce26d6476c95d484ec452b55bfbca55ba93887c5b91044eb9513941213
font_02_sfnt_off00015cab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15CAB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1