Malicious PDF — malware analysis report

Static analysis result for SHA-256 e08dc4f0de84161d…

MALICIOUS

PDF

84.1 KB Created: 2021-09-07 10:26:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5e55d5941f44a4ffc2962536a32a799b SHA-1: 004450c20f92fca71d94945791f60d05f833c1a9 SHA-256: e08dc4f0de84161d5afe8c2dfbacad972cbeadfc4535f1c20dc27b6bfcc6e627
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The sample is a PDF containing embedded JavaScript, which is a common technique for exploiting PDF vulnerabilities or delivering malicious content. Multiple heuristics indicate the presence of link farms and compromised upload storage, suggesting an attempt to redirect users to malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely involving exploitation or phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://catamma.ru/uplcv?utm_term=euler+graph+theory+pdf
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609b050b61140---berefir.pdf
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160711230dea0f---nipudewonewiwilixofanute.pdf
    • http://peneleos.pl/userfiles/file/43853708159.pdf
    • https://cafeau1ait.xyz/js/ckfinder/userfiles/files/8023875829.pdf
    • https://przyklejki.pl/userfiles/laviginudawixarotulawuv.pdf
    • http://damoorefamilyreunion.com/clients/7/71/71c8bb141a0941b69292984b9770a174/File/20418672461.pdf
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/48ca954f2418e6f2b22fcef4d12db782/bakixin.pdf
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7b1d86c080---433079779.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a57e5a8185b---86601429212.pdf
    • https://africanresearchcenter.com/userfiles/file/sunopuk.pdf
    • http://studiolauramoschini.it/userfiles/files/xosigofixivo.pdf
    • https://giraffeng.net/infodaily/gen-ckfinder/userfiles/files/74767946984.pdf
    • http://xn--80age2amlc.xn--80adxhks/pics/images/file/54947302124.pdf
    • http://email-database.info/userfiles/file/bowizusezonar.pdf
    • http://cecev.com/stockages/files/gomokos.pdf
    • http://ruiqingchem.com/upload/files/dopuxapagofuneko.pdf
    • https://jackyrouxmethode.com/userfiles/file/guxexolugiwezilotofabuv.pdf
    • http://ikkosushi.com/uploads/files/24517269083.pdf
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608381e72728e---22027641140.pdf
    • http://www.ktgroup.co.uk/ckfinder/userfiles/files/zigoxofol.pdf
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e1e990761eb---18989368428.pdf
    • https://adlinefor.com/home/webagen/public_html/korn/data/file/mepapebuwubejanosetinoriv.pdf
    • http://lafayetteconnections.com/clients/52818/File/litonanumuzivote.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_off0000df0d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF0D 16792 bytes
font_01_sfnt_off0000f724.bin
35a7db41f3b7a57c6af46776aa729994d0891c3aee2e67a4c81ccfdcfedead6b
pdf-font-stream PDF embedded font (sfnt) at offset 0xF724 10612 bytes
font_02_sfnt_off00010f4f.bin
745049ad3a57f0ee70a65428751bd1832f71afe4b648ec6330fde9f129fe2ec2
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F4F 19728 bytes