Malicious PDF — malware analysis report

Static analysis result for SHA-256 1660a0f059487ece…

MALICIOUS

PDF

76.1 KB Created: 2021-09-13 15:36:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: b47db2aac046d2329a35ab398f3740a7 SHA-1: 329bde8c88602fd2ed736e8c297f73b540292f07 SHA-256: 1660a0f059487ecef76bf4f110d2270e0f9f53d646612ac46e0574fe6213f8eb
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains embedded JavaScript, which is a common technique for exploiting vulnerabilities or redirecting users. Several heuristics indicate the PDF is part of a link farm pointing to compromised WordPress sites and disposable hosting, suggesting a phishing or malware distribution scheme. The ClamAV detection and ML classifier further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://hadt.vn/upload/files/fipekimokefoluti.pdf In PDF document text
    • https://indicaperu.com/userfiles/file/40339703417.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b09f75afd4---fodekunixuwimomegi.pdfIn PDF document text
    • http://dtmaso.com/public_html/Imagens/file/22832410959.pdfIn PDF document text
    • http://garageanything.com/js/upload/files/4432098496.pdfIn PDF document text
    • http://chinalabware.ru/d/files/nerikoxomisakejusew.pdfIn PDF document text
    • https://www.sexualaufklaerung-schule.ch/ck/ckfinder/userfiles/files/44392264409.pdfIn PDF document text
    • https://cmflower-kkc.com/ckfinder/userfiles/files/39813550367.pdfIn PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/eoa3tu1b4u2eimfaav6ia77996/kebukajisawo.pdfIn PDF document text
    • https://holocaustresearch.pl/nowy/photo/file/merezosovavaxefom.pdfIn PDF document text
    • https://eol.org.pe/ckfinder/userfiles/files/27373962412.pdfIn PDF document text
    • https://sankaibearing.com/userfiles/files/mogelobu.pdfIn PDF document text
    • https://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/f57f8b1f09f0bd1ea0f02a0823803738/90874100136.pdfIn PDF document text
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16130add5002c4---56067251675.pdfIn PDF document text
    • http://asztalosweb.hu/userfiles/file/bopiwugolenug.pdfIn PDF document text
    • http://tjchenxing.com/filespath/files/20210910224954.pdfIn PDF document text
    • http://dansungsala.com/uploads/files/befuzovekoberalob.pdfIn PDF document text
    • http://schokofontaene.de/idata/11573165647.pdfIn PDF document text
    • https://ww150004.linebot.net/upfile/files/20210912192959.pdfIn PDF document text
    • http://celyroknaterase.sk/editor_uploads/system/files/90162475992.pdfIn PDF document text
    • https://maychieuvinh.vn/upload/files/vajokidikaripelovepalej.pdfIn PDF document text
    • http://diencongnghiepvohoang.com/uploads/files/zeketokefuxewiletisa.pdfIn PDF document text
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161368c5744917---voxelopukajopagosinelor.pdfIn PDF document text
    • https://abss.pt/userfiles/file/wuzek.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=free+pc+offline+games+download+for+windows+7PDF 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_off0000c4a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4A7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dcbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCBE 10976 bytes
SHA-256: 39f94259756a1cc756c77a9201baa04a4171d606c85aab7d66ddc0dd7a920ce7
font_02_sfnt_off0000f60b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF60B 17152 bytes
SHA-256: 97420ca6f9c0b8feceb4c9729f5619495c07615fd6386fe8f8682897ccc89980