Malicious PDF — malware analysis report

Static analysis result for SHA-256 814b931f19d455f6…

MALICIOUS

PDF

82.2 KB Created: 2021-07-12 16:03:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cfdaaa30f5cac1fc40999a6d426432f0 SHA-1: bb4162fc6790cea5b30e2ee361e815ed496cd066 SHA-256: 814b931f19d455f691a629fd61decc7fa085450641c429f2a856d7b6a766404f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1055.012 Process Injection

The PDF file was flagged by ClamAV as 'Pdf.Phishing.Trojan' and an ML classifier indicated a high probability of maliciousness. It contains numerous links, many hosted on compromised WordPress sites, suggesting a link farm designed to redirect users to malicious or phishing content. No scripts were extracted, but the structure and URL patterns are indicative of a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9897

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://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/160d5af1955bed---48647238150.pdf
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160d702f66b101---xoxawejozapadutosafobev.pdf
    • http://dienmaythanglong.org/uploads/files/bilomurinezovikedajegawa.pdf
    • http://lukoilmarine.com/ckfinder/userfiles/files/gosajaluridasulivusajave.pdf
    • http://hobbstownis100.com/clients/6/66/66141d04a4341350d76ae3a38785cb5a/File/30314443076.pdf
    • http://royalgroup.at/tmp/66490362909.pdf
    • https://marcuspietrek.de/MARCUS/files/file/14995543340.pdf
    • http://jngf.cn/files/file/tapuwomifalavi.pdf
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a30ba7607be---tudisur.pdf
    • http://dambi.pl/userfiles/file/39065307058.pdf
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a99f17cd125---julibov.pdf
    • http://anhuifan.com/upload_fck/file/2021-5-18/20210518232322267118.pdf
    • http://geyikkimya.com/userfiles/upload/file/rewuvisopuja.pdf
    • https://pindimana.in/uploads/file/laboje.pdf
    • https://festival-bg.com/media/ckuploads/files/femulapafoferumilemes.pdf
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/3b91c8fe86c7160ad45c45412f285c45/56708511194.pdf
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/160afae711e21b---bawagoxabekok.pdf
    • http://loveperfectionschool.com/upload/file/33835688478.pdf
    • http://adabaskimerkezi.com/upload/file/ladodirun.pdf
    • http://dioceseofniranam.org/userfiles/file/lepuxuno.pdf
    • https://kovosluzba-praha.cz/res/file/foretikoxaxivoda.pdf
    • https://olterus.org/contents//files/gupasabawi.pdf
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/tmp/navagib.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=red+frown+face
    • 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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c1d4.bin
4dc7295e5d33dd54997c02a4fbf41f3159e8abdc0f40c94275ed1522beb19985
pdf-font-stream PDF embedded font (sfnt) at offset 0xC1D4 1744 bytes
font_01_sfnt_off0000ca1b.bin
d68a6858c4bf8a302831720713f7704006fb0e25fe2dbb82676b0d9bc7409350
pdf-font-stream PDF embedded font (sfnt) at offset 0xCA1B 16556 bytes
font_02_sfnt_off0000f51c.bin
5f5d43d59bc3c43a3ddb39bfb20a6972f3b460abce910f341186a9f08598c082
pdf-font-stream PDF embedded font (sfnt) at offset 0xF51C 10196 bytes
font_03_sfnt_off00010c26.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C26 16792 bytes
font_04_sfnt_off00012437.bin
3e1a5c08b99c48cfa263cac2d0fa4fd7eb77e98f3e485c9afca6077663a68f55
pdf-font-stream PDF embedded font (sfnt) at offset 0x12437 16660 bytes