Malicious PDF — malware analysis report

Static analysis result for SHA-256 2623682a4c198c5e…

MALICIOUS

PDF

84.6 KB Created: 2021-09-07 05:55:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 2779a1e0454074d080518479287e59ed SHA-1: 5f305d6d1bd37287e5741c4e41481224d081f2ec SHA-256: 2623682a4c198c5eaf5f06f539a7c26d20bc66429ef8ab4ef6ae45d7b8b16356
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to domains flagged as potentially compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery through these links. No scripts were extracted, but the structure and URL distribution suggest a link farm designed to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://gpe-el.pro/ckfinder/userfiles/files/98794666778.pdf In PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/9b1r4gn8d4jd45jbq5csqvha05/zumonoz.pdfIn PDF document text
    • https://bnbtravels.com/ckfinder/userfiles/files/83996829415.pdfIn PDF document text
    • http://drairtools.com/ckfinder/userfiles/files/fusuladaterem.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160960a36d217f---89865997436.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/16077e920787e2---tonapopaworanekujenupabu.pdfIn PDF document text
    • http://eternaseguros.net/files/files/47615692921.pdfIn PDF document text
    • http://www.szphotar.com/admin/img/files/dorezezugalinifejo.pdfIn PDF document text
    • https://classicandcamper.co.uk/wp-content/plugins/super-forms/uploads/php/files/q415tnp170ui2kp12f7dvi8j7g/37385817412.pdfIn PDF document text
    • https://ctapigroup3.com/contents//files/6036027104.pdfIn PDF document text
    • https://interstudy.net/userfiles/file/98780042447.pdfIn PDF document text
    • http://qunjl.com/userfiles/files/41145650803.pdfIn PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ada2a11512b---34586510854.pdfIn PDF document text
    • https://aimara-bg.com/userfiles/file/rokibobebe.pdfIn PDF document text
    • https://aspaeng.com/files/image/files/jemekepidaluvigel.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/leee5edqrl3itsgnsjr6tqjei6/70119604139.pdfIn PDF document text
    • http://phillipwhiting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c82f8dde6c---wadolu.pdfIn PDF document text
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/333c115725199a6f4b5e9d294b2ab1f4/nitorevir.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160e968291b0ab---3035597959.pdfIn PDF document text
    • https://autopsrus.com/ckfinder/userfiles/files/vamos.pdfIn PDF document text
    • http://beiwendq.com/userfiles/file/nosuvapobomexiruto.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/7hqi6j92h1hq068trl9u5bpff2/50125380801.pdfIn PDF document text
    • https://zifu-tech.com/app/webroot/userfiles/files/nafefugovulixipajof.pdfIn PDF document text
    • https://www.bistro-e.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075e3c092700---70690366190.pdfIn PDF document text
    • http://gadkowski.pl/repository/filemanager/file/wilovaramizunulazer.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=2018+calendar+by+week+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_off0000e469.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE469 10972 bytes
SHA-256: a020ae73cc2c8b5425c640b3ffa383a4be1d52dad2fcc20445e82c5d61087ffd
font_01_sfnt_off0000fdfa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDFA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001160c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1160C 17764 bytes
SHA-256: 7aae4e8339439e8f2c8f94564c9a4b6f2a1105948f45126af710d07eafc963eb