Malicious PDF — malware analysis report

Static analysis result for SHA-256 861aeef4b9e7b647…

MALICIOUS

PDF

83.2 KB Created: 2021-09-22 17:48:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 80cb071e265f3ed12cc3e6fa416176e3 SHA-1: 1c3edd1861819ebc2f9cf269c15114fca05b041f SHA-256: 861aeef4b9e7b647a1cc2e67c4e4c82a6a42a55f3accb4e2331f0d2a11f13746
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, many of which are hosted on compromised WordPress sites. The presence of 'utm_term' parameters suggests a phishing or SEO manipulation attempt to drive traffic to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://huntic.ru/uplcv?utm_term=toolbox+unlock+premium+apk PDF link annotation
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d61a83fd9d---sukuraji.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161332210e8056---tululutanivexikodi.pdfIn PDF document text
    • http://thuaphatlailongthanh.com/upload/contentFile/minhchau/file/8830117112.pdfIn PDF document text
    • http://kancelaria-perfect.pl/app/webroot/media/files/98731750772.pdfIn PDF document text
    • https://gogreenonline.net/userfiles/image/fckeditor/file/78814738874.pdfIn PDF document text
    • http://lmtechsolution.com/userfiles/tafebemuzorive.pdfIn PDF document text
    • http://it-hair.com/userfiles/29760112605.pdfIn PDF document text
    • http://fotofolliasanlazzaro.it/userfiles/files/dilufibon.pdfIn PDF document text
    • https://lanna-flyingclub.com/ckfinder/userfiles/files/titiwilelufudurega.pdfIn PDF document text
    • https://landtop.com/filespath/files/20210919132129.pdfIn PDF document text
    • https://granitnet.hu/editor_up/zenezibexuji.pdfIn PDF document text
    • http://didaconcept.com/admin/fckeditor/file/93341560608.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161481fb601327---pegawupikimikusenali.pdfIn PDF document text
    • http://clingac.es/d/files/42025120052.pdfIn PDF document text
    • http://studiodara.eu/userfiles/files/47884064251.pdfIn PDF document text
    • http://gamboeng.com/assets/ckfinder/userfiles/files/89049419324.pdfIn PDF document text
    • https://duragloss.pl/userfiles/file/vobububanifuwezo.pdfIn PDF document text
    • http://minhledtran.com/luutru/files/9472477999.pdfIn PDF document text
    • http://j-line.ca/fck_upload/file/pirobekere.pdfIn PDF document text
    • http://china-shengbang.com/upload_fck/file/2021-9-22/20210922174827374420.pdfIn PDF document text
    • http://www.tecnotrefg.it/wp-content/plugins/formcraft/file-upload/server/content/files/1612fdb786f789---3264776439.pdfIn PDF document text
    • https://alzubidi.com/userfiles/files/41564359176.pdfIn PDF document text
    • http://arqing.es/ckfinder/userfiles/files/36031867657.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_off0000dd33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD33 19100 bytes
SHA-256: baaed3b2403591114df78a6b5044c758dbd390f6ace5258bbaa5c2091350d55b
font_01_sfnt_off00010f0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F0D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012724.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12724 10664 bytes
SHA-256: f9a0916dca57b7c59178d1fb2e32dc5152025fe872c670e0dd9f3ae5d6f815f0