Malicious PDF — malware analysis report

Static analysis result for SHA-256 0857b177e04d4a02…

MALICIOUS

PDF

138.0 KB Created: 2021-07-31 03:57:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 9f9db4795f18a3cc914f35bb2bb730ed SHA-1: d552f01077d7c6fcb41427c47ee5f2698368d6be SHA-256: 0857b177e04d4a02948e14f75a23172e906feca5d28403670472ede43018f34c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9925

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://www.tvmreza.tv/ckfinder/userfiles/files/jevuritifemuxonijili.pdf In PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c91ecb7b6bb---61024983405.pdfIn PDF document text
    • http://nanobubblevietnam.com/uploads/userfiles/file/sixokobitomolinegi.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/160d6a2afc3620---navakolod.pdfIn PDF document text
    • http://lakes77.com/clients/47041/File/melavuzadibulimejazebi.pdfIn PDF document text
    • http://autodilykanka.cz/cmsimple/images/file/64739687972.pdfIn PDF document text
    • http://wang023spa.com/userfiles/202107file/2021072510560870554.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160864a9a19457---sigen.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073be5acc52f---24918887162.pdfIn PDF document text
    • https://dungcuruamui.com/wp-content/plugins/super-forms/uploads/php/files/pbfc61sq5oi4efmgpqvns43n3m/19265652717.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ba64e29570---68705337532.pdfIn PDF document text
    • https://tdsns.ru/userfiles/file/31774970655.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/160f5064a2d9dc---fozapazen.pdfIn PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/ac345441d34f7bd5948ee63543a5ec17/96351123150.pdfIn PDF document text
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdc1fc207af---fotivagetuxejodol.pdfIn PDF document text
    • https://vcvscr.cz/www/www/fckphotos/file/8472786564.pdfIn PDF document text
    • http://anhuizhkj.com/upload_fck/file/2021-5-24/20210524150009156597.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2b1b44b0fe---poremivawimutufureg.pdfIn PDF document text
    • https://martabaktelor.com/contents//files/zukodogufiparadijewakasin.pdfIn PDF document text
    • https://lcd96.ru/wp-content/plugins/super-forms/uploads/php/files/7e101c11d9342919e2be0eef47448bed/59745318391.pdfIn PDF document text
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/58636cc56ab24ebdbfc4a20598d22fd1/46006421698.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/1609493384eac9---dilolivuvosijimisidopejuv.pdfIn PDF document text
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/ab8ee178aba275a19bff970da3315c19/polakozugevajakogudegak.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=structural+geology+textbook+pdfPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00019779.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19779 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001af8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1AF8A 16680 bytes
SHA-256: ec0286af43a78251a320f5460fba9f54ab9ef9499c5b794c0c2554acf038b9b4
font_02_sfnt_off0001c73b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1C73B 11052 bytes
SHA-256: e3fdf2bc1608eee0a23dc7f149ac4d7e8132e4f48c3b4bf55573177509b886a1
font_03_sfnt_off0001e0c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1E0C9 22152 bytes
SHA-256: d7981c609bf25b2bb5a0a82f8256d8ff5eeab60ce1f596ec8bf0263d007284ba