Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4ef52e16189390c…

MALICIOUS

PDF

74.8 KB Created: 2021-06-26 01:45:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 367dfdeac89fd86e677b09a6d3258b09 SHA-1: 1f74a6e140eec44e6a864a6ed72c82b4a6b99b5b SHA-256: a4ef52e16189390c7d352808265a2dee48317f94accbf6fcba10b1ca5f40e1f8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious sites. While no scripts were explicitly extracted, the nature of the links and the detection suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://feynburg-uhren.de/uploads/9584281999.pdf
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1c01288c6e---wemonadef.pdf
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/07eej6dosffjs6u0eh2j9k93o3/kabumofun.pdf
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160826ccfcf8e2---zaxiposigazuriwewa.pdf
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/h77c0ec4vvt3os1as0oiceofci/butawugejibepi.pdf
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/183ce8a1556f066ba8bfac6fdf187df7/3275258790.pdf
    • http://akcjonariusz.com/UserFiles/file/14481129366.pdf
    • https://genesisbehaviorcenter.com/wp-content/plugins/super-forms/uploads/php/files/77e15e2bb2e76da1b84078e61e4b1ecd/761980542.pdf
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/af788397561a0b73f7ebede10eff11c0/togefoba.pdf
    • http://timandlor.com/userfiles/file/37793542885.pdf
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/a30ac83e1275239e0d7cf286e9e48553/rateponawujotol.pdf
    • https://kaptenhoki.net/contents//files/pavizinirijagoxid.pdf
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16093d390d6dad---60704048658.pdf
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160a650bacea9a---zojuraranoleliropalonamaz.pdf
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608356ea3a14a---1494990023.pdf
    • http://ildongwire.com/userfiles/file/65142761097.pdf
    • https://gservicepz.com/wp-content/plugins/super-forms/uploads/php/files/f01a00865d1bade7987946116ece534c/vuxiziderexu.pdf
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/6ce5e61979fc8f250c462a923cea8a12/49183942118.pdf
    • https://aiaciran.org/cache/fck_files/file/15968031251.pdf
    • http://tai-yang.tw/taiyang/upload/file/43155287187.pdf
    • http://stinpo.com/ckfinder/userfiles/files/41345247295.pdf
    • http://www.orhancoskun.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cae11641379---45120227915.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=rational+meaning+in+tamil
    • 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_off0000c13d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC13D 16792 bytes
font_01_sfnt_off0000d954.bin
a76ec4ef937e076f40e36759cdeb2805d87ac6cd2b6ba1c8be51282a892f6129
pdf-font-stream PDF embedded font (sfnt) at offset 0xD954 10228 bytes
font_02_sfnt_off0000f040.bin
f9488f9aa2555b5678a4a793213eb323905d62cb7648f9a14527a34fc01b1c9a
pdf-font-stream PDF embedded font (sfnt) at offset 0xF040 16984 bytes