Malicious PDF — malware analysis report

Static analysis result for SHA-256 657032ed15999aba…

MALICIOUS

PDF

80.1 KB Created: 2021-09-17 15:55:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 456bc274f0a67157d99a72c4e6dc7fb5 SHA-1: ba7bd3a9366c07da1f8ed458647a3eac57caa421 SHA-256: 657032ed15999aba0ae1985341276e5a9aaf3ac49c6fb03bbdb2df2270731a4d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a significant number of external URIs and link farms, many hosted on disposable or compromised domains, indicating a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were explicitly extracted, the presence of numerous URLs pointing to potentially malicious content supports the classification as a phishing or malware lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://chcial.ru/uplcv?utm_term=nc+go+tablet+apk
    • http://hanart21.com/files/userfiles/file/kixofit.pdf
    • https://ketex.com/trcgp/ckfinder/userfiles/files/wodenuxepupu.pdf
    • https://xn--fct5g39pjpo.tw/upload/leakstop/files/77881307679.pdf
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/1613c647cc753b---wetik.pdf
    • http://esenkardeslerinsaat.com/resimlerfiles/popubabonixusutorebosaf.pdf
    • http://4bzsoftware.com/Images_upload/files/86690006194.pdf
    • http://www.egymast-segito.hu/uploaded/fck/file/68652824037.pdf
    • http://kanalizace-ul.cz/userfiles/file/77191991475.pdf
    • http://greentreeprep.com/cote_dor_import/admin/ckfinder/userfiles/files/borafupujeludeposozezega.pdf
    • http://jilienjrubin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/30212264965.pdf
    • https://optical-axis.com/uploads/files/202109020520076704.pdf
    • http://heryeryesil.com/resimlerfiles/50176592177.pdf
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/ae232849c56c9b9202fc8b7921b63fe3/dikupulesedewedek.pdf
    • http://cngwalk.com/fckeditor/userfiles/image/60704438392.pdf
    • http://gptools.net/userfiles/file/pewadejurasumanoziredisi.pdf
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133c0ef76d0c---26039579035.pdf
    • https://marblo.ph/app/webroot/img/files/28151780589.pdf
    • http://wildpflanzen-planung.de/file/74926300798.pdf
    • http://elma1.ru/!upload/files/84150391545.pdf
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/a097f99a026b63f03f7e46ece3f19e3b/36748342506.pdf
    • http://cluster006.ovh.net/~greeters/be/ckfinder/userfiles/files/78706643916.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d420.bin
1282507ca01225ab09a3e93605dba00e0d435fdd419c3769735bd267496153f6
pdf-font-stream PDF embedded font (sfnt) at offset 0xD420 10292 bytes
font_01_sfnt_off0000eb4a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEB4A 16792 bytes
font_02_sfnt_off0001035c.bin
8c9a081ddfaf47eec852ff7d2ce7ab196cfd13d2bb284335bbf8f013223923e8
pdf-font-stream PDF embedded font (sfnt) at offset 0x1035C 18436 bytes