Malicious PDF — malware analysis report

Static analysis result for SHA-256 9112d128f439d939…

MALICIOUS

PDF

72.1 KB Created: 2021-09-04 10:18:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 9167a8514bd2df62f687ffe310c6df8a SHA-1: 6be5f17e1ef7b3bf60afd5ba0442dc8e1b96b08d SHA-256: 9112d128f439d939726688847037454e3d76998f69f982c245586a5d4a97accc
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised CMS upload directories, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were extracted, the structure and URL patterns are consistent with a malicious link farm designed to lure users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 6

  • 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.
  • 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://go-forum.cn/upload/files/vevaxowotoki.pdf In PDF document text
    • http://posekatzahradu.cz/files/file/zazexupajep.pdfIn PDF document text
    • https://www.m2asolutions.com/wp-content/plugins/super-forms/uploads/php/files/c4fccb9e11b794ff0a08cd574baa64b0/32171107258.pdfIn PDF document text
    • http://eldorautomaticgates.com/UserFiles/file/wonuwatuxelotafomuzuvipe.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c9c2efc2fc8---tuvozifawizapikuvotuzizu.pdfIn PDF document text
    • https://iescolumbus.org/wp-content/plugins/super-forms/uploads/php/files/911568b88fd859aedf3a7effcd36a555/46192883160.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/16073454075f47---mujepotote.pdfIn PDF document text
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/pg9m1jb3afnrnblj1dk3404s1l/nuxuweridab.pdfIn PDF document text
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/7e3bb0c5d5875c2fdf42f5858cd89197/didarafenakovedo.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1607724d2bfdee---rixeso.pdfIn PDF document text
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/b88af9a6f3f997aa49eb0d3681832bb5/lixufowutovux.pdfIn PDF document text
    • http://skup-laptopow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e557d923be---97626582313.pdfIn PDF document text
    • http://www.ssc-ras.ru/ckfinder/userfiles/files/90164180189.pdfIn PDF document text
    • http://naphogacomposite.com/upload/files/56284407927.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8028ab4d5e---30194898680.pdfIn PDF document text
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1c42727c81---rutalexi.pdfIn PDF document text
    • http://patp1ryb.ru/media/file/74469800370.pdfIn PDF document text
    • http://brilsports.ro/userfiles/file///51687574648.pdfIn PDF document text
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607023a2a990d---82000329816.pdfIn PDF document text
    • http://eventclub.pl/userfiles/file/rofodubufekamatet.pdfIn PDF document text
    • http://monikaknoblochova.com/userfiles/file/46986198764.pdfIn PDF document text
    • http://snotlicker.com/clients/10243/File/77268915387.pdfIn PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/96cdb9bd7c70c8c6dbb025cfcf33afc6/79393222737.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/16091adb215450---35223383289.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608af3858f3dd---pevaxoletabobufegewaxe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=unidades+de+flujo+magnetico+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_off0000b705.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB705 17216 bytes
SHA-256: 9ec760a57ba8bd904e2281c60e526ef9f1d06c56fe8ccb7867f2561552068ee8
font_01_sfnt_off0000e157.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE157 11100 bytes
SHA-256: a6f85a6a8cf4944ed22e07db9c3ff6fdb789e8d66b6900cf202d381859181c59
font_02_sfnt_off0000faf9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAF9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1