Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c4acf1108502e6f…

MALICIOUS

PDF

86.4 KB Created: 2021-06-28 14:20:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6afdd891eeb91c769657928baba20345 SHA-1: 30fd5c306041075afc94d7749d60bb080acf6e5e SHA-256: 4c4acf1108502e6fc0630d2e866e132a3502388e9d7d7a69dd82bce8e1d23c53
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm with numerous URLs pointing to various websites, many of which appear to be compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were directly extracted, the structure and URL patterns suggest an attempt to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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 http://gdlianyu.com/uploadfiles/file/rugikivomudu.pdf
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089aa38ceb26---baxoxuvu.pdf
    • https://alllegaltask.com/wp-content/plugins/super-forms/uploads/php/files/9bdrl8diucmj2qamt7ffqmuusq/tubodimudonoxidape.pdf
    • https://www.amiunaorchestra.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607f160f03a20---fupirofewagagawotib.pdf
    • https://horizontire.com/userfiles/file/12118270108.pdf
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a426957356a---kidigepaduxulonoxaduti.pdf
    • https://nhathuydesign.com/wp-content/plugins/super-forms/uploads/php/files/pqhj7ekp22jjae1vmf88cr3eoe/bonufoniwidopalij.pdf
    • https://thegioidongphuc.net/ckfinder/userfiles/files/wiroxamenevapapebakalo.pdf
    • http://www.kilincsweb.hu/fileok/file/56482957270.pdf
    • https://c4ir.ae/wp-content/plugins/super-forms/uploads/php/files/5egaqcalp3397op6hstesv4470/33984829889.pdf
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160ac39cc5dad8---88254013173.pdf
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160793ca0ed430---firupirixivukerig.pdf
    • http://zatacorp.com/upload/files/monuke.pdf
    • http://sxhk365.com/uploads/file///foganapusawel.pdf
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160b799aaf06d5---dumaxo.pdf
    • http://www.zywawiara.pl/pliki/zofozaxovikofirupuki.pdf
    • http://ridendo.cz/files/file/wusuwigabidofefopaguworaf.pdf
    • https://jyapa.com/jhuoyue/uploadfiles/vedup.pdf
    • http://rajskiewakacje.pl/userfiles/file/48257644331.pdf
    • https://portsidestrategies.com/wp-content/plugins/super-forms/uploads/php/files/4bdad6b0b94a47545d48dbd9f5e2b666/pakugixubodebi.pdf
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/1608ec2155ba92---55534825743.pdf
    • http://rford67613.com/clients/a/a2/a20594cba7d6fe247bc87ef9b80620db/File/mulemutirigetoso.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=angry+birds+movie+2+silver+and+red
    • 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_off0000ed71.bin
01f0e2ce91d677678f3948f2059e39c52e6de7c26f602623961807f42926736c
pdf-font-stream PDF embedded font (sfnt) at offset 0xED71 17372 bytes
font_01_sfnt_off00011afd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11AFD 16792 bytes
font_02_sfnt_off00013314.bin
170e33b336eb9661d6cb99431d8c2f2ac6cdd8dbe62dc2993a4b4f1e5f97e83e
pdf-font-stream PDF embedded font (sfnt) at offset 0x13314 10916 bytes