Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ec1faf9deec1fc9…

MALICIOUS

PDF

93.6 KB Created: 2021-08-30 22:28:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 7ba4b1a02251870e86768c2120f6effa SHA-1: 48f243c66b18fa93f4e969a68e669b22558f38ef SHA-256: 8ec1faf9deec1fc937719352de2f2959e996b9cbb5188bd189d76666321c75de
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to potentially compromised websites or disposable hosting. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this, suggesting the document is designed to lure users to malicious destinations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://crysiq.ru/uplcv?utm_term=dempsey+cookhouse+%26+bar PDF link annotation
    • http://alotercuman.com/ckfinder/userfiles/files/87048299010.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16107db02ce786---towemawi.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/160d364bce0f24---79398352205.pdfIn PDF document text
    • http://mirandatutoringcentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160af668c7ce2d---tarekivebitegerane.pdfIn PDF document text
    • http://qiangka.com/ckfinder/userfiles/files/pikikuf.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160f514ec1215c---xadibe.pdfIn PDF document text
    • http://sentralperdana.com/file/wuzazapabuxalafugopajof.pdfIn PDF document text
    • http://westernmaki.com/uploads/files/wopijaxujerafatux.pdfIn PDF document text
    • http://smart-ventures.ch/upload/Editor_Images/files/84930805153.pdfIn PDF document text
    • https://www.tratedu.net/ssss2018/assets/143ad273/ckfinder/core/connector/php/upload/userfiles/files/0ab80a022c11e3219ee0d660ed63b680.pdfIn PDF document text
    • http://grupophi.es/uploads/files/82373042734.pdfIn PDF document text
    • https://cihangirhotel.com/upload/ckfinder/files/mufidefileripodotudeniza.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612539e8cda2e---lusavodutajotomexefefis.pdfIn PDF document text
    • http://krakow4you.pl/krakow/files/89951384389.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/160edb522503f7---9582093430.pdfIn PDF document text
    • http://braciszewska-klimek.pl/fck_files/file/zurifuketiwemujulazoxura.pdfIn PDF document text
    • https://grouptm2.com/contents//files/7866928493.pdfIn PDF document text
    • https://northwestconvention.cz/data/files/jededut.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_off0001062d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1062D 19548 bytes
SHA-256: 4363e3004e9eff1ad4f1f28b1c928b2a9f324b400752bcbd2db1c48467e98e6e
font_01_sfnt_off000139d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x139D4 10344 bytes
SHA-256: 110c564bbc86c75a2cbe6b89c7d6248a20cdab14ee7c73b217fd4a72b675c948
font_02_sfnt_off0001513f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1513F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1