Malicious PDF — malware analysis report

Static analysis result for SHA-256 18fae163ff3ce240…

MALICIOUS

PDF

92.1 KB Created: 2021-07-20 18:50:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 3ede08d665416aab96260f8343c86c09 SHA-1: c6b09aaa60961cd60da69ef5134bcf8c0f5f39b7 SHA-256: 18fae163ff3ce24064728f34a462e7f1d3ad0ce8436210f1fac168c48016c5e6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious sites. While no scripts were extracted, the embedded URLs and the nature of the heuristics point towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

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 http://learningkey.org/userfiles/kejemulejofemabetud.pdf In PDF document text
    • http://hwayinn.com/image/files/20210702_111541.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/160903c7f8a486---12969329875.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607ffa2a664de---jupedukegolejuwevimiwo.pdfIn PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/o67ik7oahvfrh235nso0vsn6nc/59639707949.pdfIn PDF document text
    • http://digimaap.com/wp-content/plugins/super-forms/uploads/php/files/u8nkst5g5efpfjku9b5tnt03op/15637748620.pdfIn PDF document text
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/n63b50gmdcnmoihe1bsit1j28k/55638039001.pdfIn PDF document text
    • http://www.microsinusectomi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ad1dad266d---kozedemurositizel.pdfIn PDF document text
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160c7826d06c7a---73143040338.pdfIn PDF document text
    • http://kameleonhastanc.hu/files/file/64421711996.pdfIn PDF document text
    • http://mitcostruttori.it/userfiles/files/61837474087.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160aa02e2c88c4---83185372575.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be337b812c2---58840698523.pdfIn PDF document text
    • https://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/3f68540850fb161df939a1179882877e/75292162349.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/160915ad12d77c---17322689253.pdfIn PDF document text
    • https://euroroma-bg.org/files/file/25153745939.pdfIn PDF document text
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/160e7b910c814e---wifukemuzadeda.pdfIn PDF document text
    • http://kielcenoca.pl/files/file/68219697440.pdfIn PDF document text
    • http://podiummoda.ru/userfiles/file/22033552030.pdfIn PDF document text
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/p528h7045ablvic35btblblkq4/57707162236.pdfIn PDF document text
    • https://www.hinogas.com/wp-content/plugins/super-forms/uploads/php/files/9cjoggtnjuj0ea399no54fp9b9/gesopujipigon.pdfIn PDF document text
    • http://araonline.hu/uploads/file/12436663108.pdfIn PDF document text
    • https://designcoordinators.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080196e7129f---nuruzozexaxigofojozajorox.pdfIn PDF document text
    • https://ayurvedaemart.com/uploads/file/17754850093.pdfIn PDF document text
    • http://www.maderas-navarro.com/ckfinder/userfiles/files/pesole.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=top+strongest+dogsPDF link annotation
    • 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_off00010885.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10885 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001209c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1209C 10232 bytes
SHA-256: d0bbdb4596a7d6cd7c440e9cac0ffb0342d7eca5463c3f17e6500765f9f9b023
font_02_sfnt_off0001377e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1377E 16996 bytes
SHA-256: e44faa58eafbc5c905cf0bdcba02181445f281dfc944dd055eb7f31c2e82641c