Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff85cbb9ccbf43c9…

MALICIOUS

PDF

71.9 KB Created: 2021-09-25 09:13:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cd74ae57997ca742ee23718b1347e364 SHA-1: 57d44232f426e1dca4b478ef9a24a36ac7c0f810 SHA-256: ff85cbb9ccbf43c99a02e5ca0885652c6f2752c0004b3870707aaf848ed42ccd
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, with a high-confidence heuristic identifying a link to a compromised WordPress upload directory. Many other links point to disposable hosting, suggesting a phishing or malware distribution attempt. The ClamAV detection and ML classifier further support its malicious nature. No scripts were extracted, but the embedded links are the primary attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • 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.
  • 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://tarzminder.com/resimler/files/27413898803.pdf
    • http://kleinschadenexpert.com/userfiles/file/jonegoruleveras.pdf
    • https://ppuhperspektywa.pl/files/edytor/file/7106787249.pdf
    • https://eghamatsafar.ir/basefile/eghamatsafar/files/81673630796.pdf
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/g5qn4qs2vtj77rsdcpe0t9gq69/jenova.pdf
    • http://bartuceviri.com/userfiles/file/38261358639.pdf
    • http://hangnhatbanonline.com/upload/files/64765408642.pdf
    • http://nedvizhimost-v-sharm-el-sheikhe.ru/uploads/files/tedirosezatujugusogap.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/1hiaiv2mtu8g6tlplb2j605s67/92728611935.pdf
    • http://ciarajewellery.com/editor_upload/file/nosog.pdf
    • http://horizonpestservices.com/userfile/83735723834.pdf
    • https://aromamarketing.md/img/files/rekisof.pdf
    • https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/d4212fd3ce8780256fc04dfc5016d7f7/15734642636.pdf
    • http://tainanrup.longi.tw/uploadfiles/files/20210921_182837_8659.pdf
    • http://jerseybankruptcylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/30022594232.pdf
    • http://gesundheit-im-blog.de/userfiles/file/gipiwajo.pdf
    • http://gurukripapublicschool.com/userfiles/file/15245556252.pdf
    • http://cybernet.asia/UserFiles/File/fuvopo.pdf
    • https://citronixdeflection.com/nbloom/fckuploads/file/tikimabiwufujixaxut.pdf
    • https://assignmentmart.com/ckfinder/userfiles/files/4292864782.pdf
    • https://hyosungulf.com/uploads/file/gevukagarude.pdf
    • http://chanakyaaerospacedefence.com/userfiles/file/womuroxotu.pdf
    • http://www.hausbaumesse.at/ckfinder/userfiles/files/32454483825.pdf
    • http://wildpflanzen-planung.de/file/68689606586.pdf
    • https://hitourkorea.com/FileData/ckfinder/files/20210917_BEFEB1D459DEA0F0.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=ludo+star+2+hack+apk
    • 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_off0000b47e.bin
365a676ab93365dfe5ebe62d34a912ed867ddea3bdb734dd8b5356761e157948
pdf-font-stream PDF embedded font (sfnt) at offset 0xB47E 10504 bytes
font_01_sfnt_off0000cca6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCCA6 16792 bytes
font_02_sfnt_off0000e4b8.bin
16d972e50bb6ecc80d64bc1ac4edcb26dcd0f956b63ce7ef46755b0f83e26b8c
pdf-font-stream PDF embedded font (sfnt) at offset 0xE4B8 17464 bytes