Malicious PDF — malware analysis report

Static analysis result for SHA-256 92a91808d6c38b81…

MALICIOUS

PDF

85.2 KB Created: 2021-09-18 20:45:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e4145b8dcab4ec79ae37533aaa6aaad3 SHA-1: 6c330f15fc38a0371e334c7bdc17628cc284e917 SHA-256: 92a91808d6c38b81cb60fea7804640037d3b4aeb6516cf569c5a4567c6a69706
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, suggesting a link farm for phishing or malware distribution. The ClamAV detection and ML classifier strongly indicate malicious intent. The embedded links are designed to redirect users to potentially harmful content, likely as part of a phishing campaign or to download further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

Heuristics 7

  • 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 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://tessuno.com/upload/files/613f97ec7635d.pdf
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/036eaf999dc8606b9ca740d45e06fe1b/64916126956.pdf
    • http://munnartourism.com/uploads/file/xojoluxajatiwifiwomowubis.pdf
    • http://kingbikeonline.com/images/upload/File/44632108671.pdf
    • http://szjg.hu/images/file/wegugoxokofinigajobi.pdf
    • http://energy-labels.com/userfiles/file/gifabidavunerezetajekori.pdf
    • https://happy-playground.gr/uploads/_uploads/files/jemujatojor.pdf
    • https://tabularasa.lv/sites/tabularasa/uploads/documents/files/xivikifixufuraregi.pdf
    • http://thebookmarkcafe.com/uploads/files/sejuzaxizubotokidigebepum.pdf
    • http://www.rosabrockenhaus.ch/ckfinder/userfiles/files/repajivimikedudigelo.pdf
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161440fab4fd32---12516784853.pdf
    • https://songhong-thudo.com/img/files/12632624123.pdf
    • http://saktigroup.in/uploads/zavovap.pdf
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613a9bde1a61b---38309272787.pdf
    • http://hangquangauto.com/files/87699373224.pdf
    • http://carraracucinecomponibilitrapani.it/userfiles/files/pexixej.pdf
    • http://cuakeobinhduong.com/upload/files/51472648652.pdf
    • http://youngdongtec.com/userfiles/file/44001956150.pdf
    • https://groupburuemas2.com/contents/files/jarevuzo.pdf
    • https://www.natursany.com/ckfinder/userfiles/files/tewagakewepovububezanav.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=onlyfans+premium+free
    • 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_off0000e7ce.bin
603372240aa97604fa061a993eae1e4c0e74113982a59e959c8367ffaac9f8e6
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7CE 10540 bytes
font_01_sfnt_off0000ffd6.bin
0dddfb7a1419607ec57faaf8c507fe45710fd1cd85b2f00d25c79ce725e9df6f
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFD6 18320 bytes
font_02_sfnt_off00012f98.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F98 16792 bytes