Malicious PDF — malware analysis report

Static analysis result for SHA-256 a115c44adb36abf6…

MALICIOUS

PDF

70.8 KB Created: 2021-09-27 01:15:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9792cee2ed048fda16357f5577614184 SHA-1: 4fcb0c6e4dc6da4b6fab5371ec0d8281e4171261 SHA-256: a115c44adb36abf6709c68b5df72e927621e46d36edce9279c4e0d705c9d510c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, containing numerous URLs that point to external websites, likely to lure users into downloading further malware or submitting sensitive information. The presence of external URIs and link farm heuristics strongly suggests a malicious intent to redirect users to compromised or malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://queure.ru/uplcv?utm_term=schaum+series+pdf
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613680aaa04bc---7391915152.pdf
    • http://kirakuramenandsushi.com/uploads/files/dofawavuninof.pdf
    • https://loppisidjupdalen.se/images/uploaded/file/79631680906.pdf
    • http://www.contal-farmer.com/uploads/files/furipefakijewidugeju.pdf
    • http://ordinate-ltd.com/file_media/file_image/file/toxeza.pdf
    • http://kleinschaden.expert/userfiles/file/runesefetuwaxigufesefaw.pdf
    • http://aaas.handyfriendship.com/upload/files/xulogan.pdf
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133e06ce1141---53178876007.pdf
    • https://bhiringisamsankalimandir.org/userfiles/file/zilokasixabazolumak.pdf
    • http://cuspsurgeons.com/userfiles/file/38844166003.pdf
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613ec9ad2476b---65815363016.pdf
    • http://wingtsunkungfu.ro/imagini_ws/wugivelitip.pdf
    • http://assotechne.eu/userfiles/files/31308336999.pdf
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/16146e0f8d44e0---41855606596.pdf
    • http://fongyoskert.hu/userfiles/files/bupogotozalofamozan.pdf
    • http://gabinetpro.gabinetpro.pl/kosmetyczka/krakow/files/64936484126.pdf
    • http://ahzycw.com/upload_fck/file/2021-9-10/20210910001940848275.pdf
    • http://peaceinsrilanka.lk/ckfinder/userfiles/files/musisafanutegel.pdf
    • http://mitcostruttori.it/userfiles/files/97071690219.pdf
    • https://speculatio.in/ci/userfiles/files/fekumur.pdf
    • https://ruiguoex.com/upfile/files/2021/09/25/49082667610.pdf
    • https://rumusjitu.com/contents/files/79676969951.pdf
    • https://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/254cdf6a6c28cbf1e63d20d8b7471ac8/17173945652.pdf
    • http://daugiavanthienphuoc.com/media/ftp/file/39271759737.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_off0000b009.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB009 16792 bytes
font_01_sfnt_off0000c820.bin
565a422c0e8cb225707fdd84b4c4ea5ed1a593dac8fd48324c566351ef080556
pdf-font-stream PDF embedded font (sfnt) at offset 0xC820 10692 bytes
font_02_sfnt_off0000e095.bin
926c78c170753e986b08505d56ea443f062751fe3dc011be619be2e6c7af557f
pdf-font-stream PDF embedded font (sfnt) at offset 0xE095 16836 bytes