Malicious PDF — malware analysis report

Static analysis result for SHA-256 16912ff346d3e0f6…

MALICIOUS

PDF

84.2 KB Created: 2021-09-02 19:54:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 904ec9acb8eeba179bc945f7b3fb1ea0 SHA-1: 790719ac996e1c5ed8646b190f70a4b4090a245e SHA-256: 16912ff346d3e0f6b5fa2f987fa21f2053c7ad1c976f2fbf84c893537d75d13f
164 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains embedded JavaScript and numerous links, many pointing to compromised WordPress upload directories or other suspicious domains, suggesting it is designed to host or redirect to malicious payloads. The presence of a link farm on disposable hosting further supports a phishing or malware distribution scheme.

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 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 http://otvorene-srdce.sk/userfiles/file/xoziti.pdf In PDF document text
    • http://ineke-ott.nl/keramiek-beelden-imagesfile/piwakudasipemonefax.pdfIn PDF document text
    • http://xiaohecollege.com/d/files/fitodajoxafogopozur.pdfIn PDF document text
    • https://apparel.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/77030b8cf3f2fa83864ab48f8945d2d4/26498800534.pdfIn PDF document text
    • http://kochi-mimoto-iin.com/TakamatsuClinic/userfiles/file/kesopodawabel.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610cc61fa659d---40588645612.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c747c2a54d---pojexabimapur.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/nufurasegebi.pdfIn PDF document text
    • http://purifoy2020.com/clients/1/11/118d8b7ee1ea4bab8fb19da95c56260f/File/mufoxutipifubeja.pdfIn PDF document text
    • http://clinicaveterinariamontecchia.com/userfiles/files/29517647758.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a7e2c07e04c---salawamokololapipivizores.pdfIn PDF document text
    • http://flomojapan.com/upload/files/pazafowif.pdfIn PDF document text
    • http://musicupclose.com/clients/f/f7/f7c291dfb329fbc33054893077acf627/File/miligomiv.pdfIn PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/3d911f53861e3a2a4884eb2d73f57965/retuzow.pdfIn PDF document text
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b01eb09e922---77986941944.pdfIn PDF document text
    • http://ebd.su/UFD/7623/files/bopozitejadasekivafemu.pdfIn PDF document text
    • http://perechen-jurnalov.ru/js/ckfinder/userfiles/files/32979361218.pdfIn PDF document text
    • http://nitm.ac.in/nitmeghalaya/ckfinder/userfiles/files/funekokajibigunikimadi.pdfIn PDF document text
    • https://gadd-asso.org/userfiles/file/12272448002.pdfIn PDF document text
    • https://uniontend.com/userfiles/files/74233153618.pdfIn PDF document text
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd4d98abc1c---50372136111.pdfIn PDF document text
    • https://malashealthcare.com/userfiles/files/kudodezebulikudimimazuz.pdfIn PDF document text
    • http://konsultacjenaukowe.eu/Upload/file/15044265976.pdfIn PDF document text
    • http://saigonford3s.com/uploads/2021-07-19/images/files/kelerinasebadisabamomor.pdfIn PDF document text
    • http://aranykoronakft.hu/userfiles/file/95216081754.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=%C2%A7+10+arbschg+pdfPDF 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_off0000de39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE39 10796 bytes
SHA-256: 74570df92b6e87cb1d916fce9b4bc1275e9c1110ef6ad54b896ecfead1182012
font_01_sfnt_off0000f6c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6C9 19960 bytes
SHA-256: 800ace9d04e4c80f02099a31f2df15b9715ff13fe1175558f5ef6445d8f0d61f
font_02_sfnt_off00012996.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12996 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1