Malicious PDF — malware analysis report

Static analysis result for SHA-256 844ae8cffd641a41…

MALICIOUS

PDF

81.9 KB Created: 2021-09-21 03:45:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 422931076b96290331490ace521f4ebd SHA-1: 0d1465e8e580337bc98d9454859edea8bafa8973 SHA-256: 844ae8cffd641a413cbd85b2ea3c8cb8516bae1432aa77c47c0bd671e4204cc6
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating it likely serves as a phishing or trojan delivery mechanism. The presence of numerous links pointing to compromised CMS uploads and disposable hosting suggests a link farm designed to redirect users to malicious content, likely a second-stage payload. No scripts were extracted, but the PDF structure and URL patterns are consistent with malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://studiogalata.it/userfiles/files/petemusakik.pdf In PDF document text
    • http://aexpress.lv/index/images/up/file/gunupusulixenobiw.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/067aa0d7ce189dfd6059d13a182b1267/kasobotimijuwujobizuko.pdfIn PDF document text
    • https://parisautotravel.com/wp-content/plugins/super-forms/uploads/php/files/dt3jnmas52rji3petl5dcna584/97409617449.pdfIn PDF document text
    • https://broadcasthub.com/ci/userfiles/files/41413134179.pdfIn PDF document text
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/3f451d72427e983721fe0fe6293c2054/keragirezaduluwigogona.pdfIn PDF document text
    • http://kechengchem.com/upload/files/gijejolemuwowek.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/16137fd159a36f---78685298604.pdfIn PDF document text
    • http://enidental.com/userfiles/file/20210901175524.pdfIn PDF document text
    • http://uralteplostroy.ru/content/file/33759947017.pdfIn PDF document text
    • http://fine-cottage.ru/userfiles/files/59370536814.pdfIn PDF document text
    • https://szelvedojavitasmiskolc.hu/files/files/wanobekesarumegusa.pdfIn PDF document text
    • http://montpellier-business-plan.fr/mbp/upload/images/images/upload/ckfinder/zibekoxazawuruno.pdfIn PDF document text
    • http://watthaistuttgart.de/userfiles/file/bolabunanidijivufujosurir.pdfIn PDF document text
    • http://emotionpicturesfestival.gr/userfiles/file/12819557300.pdfIn PDF document text
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/htm97dg7sbfjs3d4jnjte9tkgg/53480805189.pdfIn PDF document text
    • http://vandervalk.reviews/app/webroot/files/userfiles/files/xamogoz.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1613f950973698---kemenoxinaw.pdfIn PDF document text
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16142d2cf33ec2---40414768455.pdfIn PDF document text
    • https://webornate.com/viking1/uploads/files/63187175786.pdfIn PDF document text
    • http://sushiloverca.com/uploads/files/xalelota.pdfIn PDF document text
    • https://sangolongphuong.vn/longphuong/news/files/60918849679.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/16147dd050a441---gokimogi.pdfIn PDF document text
    • https://daotaolaixesontay.com/uploads/file/jezirulitumal.pdfIn PDF document text
    • http://www.zywawiara.pl/pliki/44317386497.pdfIn PDF document text
    • https://westhigienia.hu/editor_up/jibuzenuruwufolibekefogi.pdfIn PDF document text
    • http://aimecostruzioni.it/userfiles/files/90613957061.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=pacer+pedometer+apkPDF 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_off0000de6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE6B 10356 bytes
SHA-256: 8aa63f1ff14b8e280b0fd31b07e78d39f3f714c29578a94128996be3a6c0793f
font_01_sfnt_off0000f5dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5DD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010def.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DEF 16956 bytes
SHA-256: 3e13dac5845d3d605e1edbc10db7a3560e8c56f4501eee38b9aaebf4683de030