Malicious PDF — malware analysis report

Static analysis result for SHA-256 f36579cc3e1ca188…

MALICIOUS

PDF

90.4 KB Created: 2021-06-26 00:51:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: eae6e94f0197e64d785bc439af6f2fd6 SHA-1: 775c9452c0b562eadc76b57edf5bf225f6b64096 SHA-256: f36579cc3e1ca18823195e5b6cb92c9f732b05be7d0439551a904474fb785f6a
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file that contains numerous links to external websites, many of which are hosted on compromised WordPress installations. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of PDF_RANDOM_URL_LINK and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports the attack pattern of luring users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://ensasoft.com.tr/wp-content/plugins/super-forms/uploads/php/files/0lfaqmgkfdr0ljle0tqb1mjm77/35589382122.pdf
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/e46f770da78225537924579c7ce6f717/jizag.pdf
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/b5d0f17eef32ef9c32e073dc7db5e1fc/pubepuburenufi.pdf
    • https://tabularasa.lv/sites/tabularasa/uploads/documents/files/90962668472.pdf
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/oe3akodi9sbmoearu6be9402i6/pewuwivajufisigunul.pdf
    • https://www.dishdivvy.com/wp-content/plugins/super-forms/uploads/php/files/f574b53fdc86e6ff7c3e3e97a5518a0d/lakage.pdf
    • http://txextremecarts.com/userfiles/file/takedexajexet.pdf
    • http://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608bcb5b6ffff---41324014471.pdf
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/1607bd18bc109a---73587164102.pdf
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/2e92d5fac9f01bc1e72ba9c77e3c26d7/xazem.pdf
    • http://navigator-33.ru/media/file/83172704967.pdf
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160702e7be9ae6---vopugagubi.pdf
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8b92fc20a9---duwuresiguwovewaxisezal.pdf
    • http://xinyaoqiye.com/upload_fck/file/2021-6-3/20210603045857966986.pdf
    • http://ambulatorioveterinarioscapindandrea.it/userfiles/files/18891056413.pdf
    • http://akkoryazilim.com/userfiles/file/domuvat.pdf
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/99294fb10c61856b10d58a1fcb951244/44754285837.pdf
    • http://rufullthrottle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609240e5eea22---femejizijatirebigikixigib.pdf
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/0l4pnd07su5c1q5vi11625tu9s/63473719629.pdf
    • https://tolgyesvolgy.hu/userfiles/file/55852116623.pdf
    • http://booklandbooks.com/userfiles/file/68218357743.pdf
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/16080cd429ea20---82126408056.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/9gl33p1jkbq19leh9qobcdn96f/felen.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=used+scamp+5th+wheel+for+sale
    • http://pro.ovh.net/~tribuene/images/banque/file/nazumat.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_off0000fb6b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB6B 16792 bytes
font_01_sfnt_off0001137d.bin
01261aac0419c5650f05e6e59f1abc153c3d58fb62add9fb461e22114b2b5958
pdf-font-stream PDF embedded font (sfnt) at offset 0x1137D 18040 bytes
font_02_sfnt_off000142d3.bin
fe446e59f451e6e216f84bd306e7bfecf6193229a4ae6fa833e23d6493059c14
pdf-font-stream PDF embedded font (sfnt) at offset 0x142D3 10916 bytes