Malicious PDF — malware analysis report

Static analysis result for SHA-256 818c1956b4a3c719…

MALICIOUS

PDF

81.1 KB Created: 2021-09-16 09:53:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 1133681bfe2ebad9dab4851c0014afa2 SHA-1: 6195ee618c5804e7ed908612b90ca7b472be840d SHA-256: 818c1956b4a3c7194d7e4a2f214b2807524d1a37844dca339738e42a13cc40cc
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs pointing to compromised websites, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of embedded JavaScript suggests it may be used to redirect the user or execute further malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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=spider+stickman+rope+hero+2 PDF link annotation
    • http://zabradli-znerezu.cz/userfiles/file/zuremume.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131f284bbbeb---gefejinotojozelabuneposan.pdfIn PDF document text
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/16140015cb0aa6---53762211972.pdfIn PDF document text
    • https://e-motorcycle.tw/upload/emotorcycle/files/toremiroxinidedunanivebod.pdfIn PDF document text
    • http://oasis-inwaste.asia/files/file/lamotakedexadewazedoxuduk.pdfIn PDF document text
    • http://gamaxmotor.cz/data/dokumenty/66446105192.pdfIn PDF document text
    • https://apsco.ly/userfiles/files/pevitusogijusawif.pdfIn PDF document text
    • http://apsons.eu/files/file/lezuluz.pdfIn PDF document text
    • https://ekoelprom.pl/public/images/editor/file/remuroganulijavemodom.pdfIn PDF document text
    • https://fereshtegan.net/basefile/fereshtegannet/files/jojewalotaximilavape.pdfIn PDF document text
    • https://tekartltd.com/upload/files/wupedogoxisijawadigo.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/s1ka6afq0bgqspqcm7cb8ljrd5/25334636220.pdfIn PDF document text
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/cu78gnujtv8se5gfnr20qj9fu5/mulumetodujudi.pdfIn PDF document text
    • https://bharatbiodiesel.com/userfiles/file/20692514972.pdfIn PDF document text
    • http://xnucleus.com/members/member_images/files/tavazu.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/16136efb2036ce---3048539654.pdfIn PDF document text
    • http://skidubravy.sk/spravca/ckfinder/userfiles/files/2622927733.pdfIn PDF document text
    • https://nhahangbienhaitien.com/uploads/files/kigejoxofobu.pdfIn PDF document text
    • http://spartapr.com/images/upload/file/81284193044.pdfIn PDF document text
    • https://strategie-forex.com/ckfinder/userfiles/files/bogikinopebakomagiwuweje.pdfIn PDF document text
    • https://serwisnawigacji.pl/userfiles/file/13167554496.pdfIn PDF document text
    • https://www.ebenisterie-burette.com/ckfinder/userfiles/files/sizefojinomalov.pdfIn PDF document text
    • https://chatsystem.site/js/ckfinder/userfiles/files/labexosa.pdfIn PDF document text
    • https://stephankeppel.com/userfiles/file/97717931745.pdfIn PDF document text
    • http://studiobaliva.eu/userfiles/files/zofokalalu.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_off0000d716.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD716 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF28 17804 bytes
SHA-256: 37dfabd99b92ca977d14a27ca4999f1a503549a47ce7c8d715fd133de048609b
font_02_sfnt_off00011d5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D5E 11020 bytes
SHA-256: 688a731c45740c1790b9742e52ee2e1f084aa82bea2e1947d6e6f36f238e81a6