Malicious PDF — malware analysis report

Static analysis result for SHA-256 227e1439d76a0985…

MALICIOUS

PDF

79.3 KB Created: 2021-09-04 03:59:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 67cefb16bf55c54839b6379442e3c6a3 SHA-1: 74e4443c806029192918ee5a4f56d14a04e42aad SHA-256: 227e1439d76a0985f43adae051e22a366becde1dc8f7f6fde89ab08b3c4af517
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm. It contains numerous URLs pointing to compromised WordPress sites and other disposable hosting, likely intended to lure users into downloading further malware or engaging in phishing activities. The presence of external URI heuristics and the compromised CMS upload link farm rule further support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://irlanc.ru/uplcv?utm_term=practical+algorithms+in+pediatric+endocrinology+3rd+edition+pdf PDF link annotation
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/2v4japsacd072gq2ks7gdse0e3/nemufomunosov.pdfIn PDF document text
    • http://el-master.ru/userfiles/file/89506686613.pdfIn PDF document text
    • http://piri-piri.pl/ckfinder/userfiles/files/pavematepawener.pdfIn PDF document text
    • http://zawayakw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095f063977cb---4678094849.pdfIn PDF document text
    • http://alphasigmaoverseas.com/userfiles/file/52980414007.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160cd58262ad04---gazebijafisulopupazoxi.pdfIn PDF document text
    • https://inclinedigital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608427684bdde---lesoxawigizogulegifizubu.pdfIn PDF document text
    • https://mamotato.ro/userfiles/file/2295094378.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1606cefe3bd900---3593563969.pdfIn PDF document text
    • https://menu2uplus.com/images/file/siruwezol.pdfIn PDF document text
    • http://maroba-zirndorf.de/file/49607475095.pdfIn PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/clmgdmvpc4h8ph776irh4i0dt1/vanivikebokona.pdfIn PDF document text
    • https://brahmagnanam.org/fck_uploads/file/42417937048.pdfIn PDF document text
    • http://ogledalata.bg/uploads/pages/files/gadazoravilasaniwiwuwunow.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c3b9ce9a44---purevonuvomodap.pdfIn PDF document text
    • http://cheapmarkt.com/userfiles/file/84011643971.pdfIn PDF document text
    • https://fishboat.hr/files/bofukivumixozilev.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/8d72f6919d075c46f325eea95a91555a/85955419570.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609ca27ed3797---145917473.pdfIn PDF document text
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ad2b4d3199f---zulevururenedutexufa.pdfIn PDF document text
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c00b8b62267---tutarakukakuwuludopakano.pdfIn PDF document text
    • http://lezeckastenakosice.sk/upload/files/mozer.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/161329b95be513---28883564649.pdfIn PDF document text
    • https://simplehome.ro/ckfinder/userfiles/files/9718223618.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d0fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0FB 11352 bytes
SHA-256: 544e4792203cef05ec90f40f52c6557aa4bd0caebadb480bdfb747ab45567405
font_01_sfnt_off0000eb5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB5B 16920 bytes
SHA-256: 2565ad2c2c8a40de814f9c5c88262fdbfa6e2295fb09305b36be5d75d3fdabf8
font_02_sfnt_off000116a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116A7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1