Malicious PDF — malware analysis report

Static analysis result for SHA-256 837743a840860abe…

MALICIOUS

PDF

85.9 KB Created: 2021-09-13 05:29:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: d88cdf8149088fdd2b90e6dbbe83c4f2 SHA-1: 766c81253a457a0c8875a2cd3463ce9a2e290b63 SHA-256: 837743a840860abebcfeac4b9e217f503932d97d56ebb171580176ac8f134838
174 Risk Score

Malware Insights

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

The PDF contains multiple heuristics indicating malicious intent, including random and SEO-disposable link farms pointing to external PDFs. The ML classifier and ClamAV detection strongly suggest this is a malicious PDF, likely used as a lure for further infection. The presence of a 'download button' heuristic further supports a phishing or social engineering attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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.
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://huntic.ru/uplcv?utm_term=vita+app+free+download+without+watermark PDF link annotation
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cb50579204---75366939877.pdfIn PDF document text
    • http://massimobertoarchitetto.com/userfiles/files/jenajesewifa.pdfIn PDF document text
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/c4sfbpfipqtanv14v1j20rcoab/87503793230.pdfIn PDF document text
    • https://ladymamashop.com/uploads/files/202109100900447344.pdfIn PDF document text
    • https://heuresromantiques.com/upload/files/gerowerijezudoritumaxizul.pdfIn PDF document text
    • http://xn--90aoj0agf7cq.xn--p1ai/uploads/files/budawerusuzukotuzififujif.pdfIn PDF document text
    • http://ambulatorioveterinariocigliano.com/userfiles/files/95734390256.pdfIn PDF document text
    • http://chocoenglish.com/_UploadFile/Images/file/2210589547.pdfIn PDF document text
    • http://zatuchlina.cz/upload/file/80291702635.pdfIn PDF document text
    • https://dalilak1.com/userfiles/file/zuverudawosu.pdfIn PDF document text
    • http://cravaluos.com/ckfinder/userfiles/files/58156822371.pdfIn PDF document text
    • http://dolekkoyum.com/admin/UserFiles/file/gonilanidubafa.pdfIn PDF document text
    • https://perfecthospitals.org/FCKeditor/file/78624211496.pdfIn PDF document text
    • http://gilendor.cz/userfiles/file/14401040654.pdfIn PDF document text
    • http://veraschwemmle.de/fckdata/file/modevovivitufaxudufotolix.pdfIn PDF document text
    • http://kkc1.org/htdocs/cljr/data/files/1650646683.pdfIn PDF document text
    • https://htijsr.com/userfiles/file/dofozir.pdfIn PDF document text
    • http://rdmsrl.it/userfiles/files/63436696186.pdfIn PDF document text
    • http://nhasachnguyenvancu.com/Images_upload/files/kolikilibenujegogej.pdfIn PDF document text
    • http://sd-admin.fazendapenaazul.com/ckeditor/uploads/files/45798345910.pdfIn PDF document text
    • http://thetestmag.com/userfiles/files/90900312855.pdfIn PDF document text
    • https://www.nevjegykiraly.hu/userfiles/files/ranelarawa.pdfIn PDF document text
    • http://mamolenasnc.it/userfiles/files/kisinimebeparexadifiregax.pdfIn PDF document text
    • https://majubesar.org/contents/files/21882605793.pdfIn PDF document text
    • http://dochoiotovn.com/uploads/userfiles/file/noweniko.pdfIn PDF document text
    • 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_off0000eadd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEADD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000102ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102EF 17944 bytes
SHA-256: 20acea1790e1b1aad82eadd73f6be9ffd2c60587257e6f188a2fb4f917121cce
font_02_sfnt_off00013118.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13118 10840 bytes
SHA-256: 175b149137dfc7ff846e76fd0b21f592f92a2dffcc90990ef7400c2af21eec28

Open this report in the interactive analyzer, or submit your own file for analysis.