Malicious PDF — malware analysis report

Static analysis result for SHA-256 ecf6780bb5413186…

MALICIOUS

PDF

72.3 KB Created: 2021-09-30 19:22:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 504aca9d3ee9867d88b836198117eb6d SHA-1: e6cd1d1d6bef6f328c000c0d30fdb686edb3f3e2 SHA-256: ecf6780bb54131869178fbdf4cf810e48f86a4b4eefc6c325293e9875c7eb939
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. It contains numerous embedded URLs, many of which are part of link farms hosted on potentially compromised or disposable domains, suggesting a phishing or malware distribution scheme. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using search engine optimization tactics to disguise malicious links. No scripts were extracted from this sample, but the presence of multiple external URIs points towards an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://allytemp.ru/uplcv?utm_term=minecraft+1.18+apk+download+free
    • http://obchodsezlatem.cz/upload/files/27177381165.pdf
    • http://maybaobidinhdinh.com/upload/files/zukuwiwagigobuzif.pdf
    • http://konstruktor33.ru/app/webroot/files/files/berisi.pdf
    • http://tkhomedeco.com/assets/uploads/ckedit/files/20210904000222.pdf
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/b80f3d2c42db1102046e39dfdfd12ccc/nivavonugejexonokozopibax.pdf
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613b3dca59848---49492131212.pdf
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614c519445be5---87642876230.pdf
    • http://angelofthewinds.net/ckfinder/userfiles/files/31961920436.pdf
    • http://ranaghatpchsschool.org/userfiles/file/deruwowor.pdf
    • https://mirrorlink.com/public/files/files/gegazagazazukogukodezok.pdf
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614071d5b9c48---95210735437.pdf
    • http://bowlingkillers.com/imgdb/files/22592854077.pdf
    • http://yigang-lin.com/uploads/files/202109011051021890.pdf
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/5cb5eac808f5339ed6554c6acd52634a/88050850379.pdf
    • https://rts-wm.com/ckfinder/userfiles/files/38092795655.pdf
    • https://urbanlivin.lu/userfiles/files/gajopakamer.pdf
    • http://hpcad.pl/Upload/file/71915511939.pdf
    • http://sparan-art.ru/ckfinder/userfiles/files/44854521994.pdf
    • http://tourhong.com/FileData/ckfinder/files/20210901_CB35F0C905B529DC.pdf
    • https://www.hinkler.com.au/application/third_party/ckfinder/userfiles/files/varoxatizavavuxu.pdf
    • http://jamalcar.com/userfiles/file/27540959746.pdf
    • http://321eastern-thailand.com/userfiles/files/56313528079.pdf
    • http://es-manzokudou.com/yamituki-n/uploads/files/gukukamaxur.pdf
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613c8c3c14ccf---bokumakepujonebakugogub.pdf
    • https://www.rt9.rspo.org/ckfinder/userfiles/files/68316397225.pdf
    • https://cakamuzejs.riga.lv/ckfinder/userfiles/files/medusaredurizu.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b4fb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB4FB 16792 bytes
font_01_sfnt_off0000cd12.bin
2dded443036baec63dc17d74e0f7ffeafda83498cfc9835330bec6867e91f606
pdf-font-stream PDF embedded font (sfnt) at offset 0xCD12 10944 bytes
font_02_sfnt_off0000e6aa.bin
bd705cf0e497b02dce0b6c85d9362e0b817e354eec386b736fd3af65ab93ffc1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6AA 17524 bytes