Malicious PDF — malware analysis report

Static analysis result for SHA-256 71336d31df9bc573…

MALICIOUS

PDF

83.0 KB Created: 2021-09-05 09:01:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: ab5abd846a9a90506ab53421769a7313 SHA-1: 316af748dc24c2f6c15c7ae4068ed060b2ff0980 SHA-256: 71336d31df9bc57317f466809398f2f99bbd1197af679e73d81e560512ee5e9d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links pointing to compromised WordPress sites and other disposable hosting, which in turn host more PDFs. This structure suggests a link farm designed to distribute malicious content, likely for phishing or malware delivery. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609e3e437d60d---80939650752.pdf In PDF document text
    • https://www.nrlandscapes.co.uk/wp-content/plugins/super-forms/uploads/php/files/feea776d6f6b1d663384a7368decf332/79345083160.pdfIn PDF document text
    • http://mwflower.com/upimagesfile///51702305797.pdfIn PDF document text
    • http://cnkls.com/userfiles/file/1626942974.pdfIn PDF document text
    • http://9jamail.com/FCKeditor/editor/filemanager/connectors/userfiles/file/56866777413.pdfIn PDF document text
    • http://omak1968.com/clients/71178/File/65777921315.pdfIn PDF document text
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/16083e4f0ddb63---84071851430.pdfIn PDF document text
    • http://szkolka-wiercioch.pl/files/file/66608308223.pdfIn PDF document text
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/cetjqsofue9rov7p2no531o977/solawexitivi.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/43d04aa915b22dc8d7edd2afe1dba7d2/gobofav.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f831160c242---weniwajobotimaleluxuxefe.pdfIn PDF document text
    • http://fszhenjia.com/upfolder/e/files/20210607164658.pdfIn PDF document text
    • http://lowdertraviscoats.com/clients/7/74/74ec8bd2877f4db8d0b9f56bae0111c3/File/66309445065.pdfIn PDF document text
    • http://ip-golubev.ru/ckfinder/userfiles/files/sawirozino.pdfIn PDF document text
    • https://khogiaydantuonghanquoc.com/images/news/file/zawotapata.pdfIn PDF document text
    • https://avigailpekelman.com/sites/default/files/file/fofiraxen.pdfIn PDF document text
    • https://advantagelic.com/singhania/downloads/file/55799000645.pdfIn PDF document text
    • http://hotechike.com/files/files/90245230834.pdfIn PDF document text
    • http://omatsuri.kr/data/userfiles/files/tupeposizutofowik.pdfIn PDF document text
    • http://dgjst.com/upfile/file/dotareledes.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a7ada32069c---vebavazatenakutu.pdfIn PDF document text
    • http://pathtojanna.com/userfiles/files/91080429189.pdfIn PDF document text
    • http://faisaltowel.com/survey/userfiles/files/82394299755.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/36b14c6b78d119e7b223d39f18f5995d/6167929925.pdfIn PDF document text
    • http://laiyi-art.com/userfiles/file/nesedazevuxutufazogu.pdfIn PDF document text
    • https://eberli-medical-supply.ch/upload/file/76606566873.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=detex+panic+bar+manualPDF link annotation
    • 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_off0000dd9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD9C 18496 bytes
SHA-256: 54774013ca87e5be9d9660b5f0deeaabde15e19c27b6ff8a5a4befabe94bb654
font_01_sfnt_off00010e3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E3C 10592 bytes
SHA-256: 728e6f45a55792c6676b920ab9d83b97dc8ffdd6d2c07d62d358009db888ceb6
font_02_sfnt_off0001263a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1263A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1