Malicious PDF — malware analysis report

Static analysis result for SHA-256 31bc369762d57dc8…

MALICIOUS

PDF

78.6 KB Created: 2021-07-17 15:06:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 050c77000251d10a801a0cea79caba10 SHA-1: 3227483699aedcb4cee0fa66b729aa78b2b3ba29 SHA-256: 31bc369762d57dc8fc0e51fb7afccad23e333f7c549f4790196fd6a0fa90cfbf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm pointing to numerous domains, many of which are associated with compromised CMS uploads or appear to be disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL targets are indicative of a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://salinahighschool1968.com/clients/3/33/33fcb9b832a528c934b1ac42c6b88a99/File/vibixesubutevitif.pdf In PDF document text
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/cb74201be85e56e536170b734c453855/62043865151.pdfIn PDF document text
    • http://efuturesthai.com/uploads/file/7186304246.pdfIn PDF document text
    • http://otohyundaidanang.com/uploads/image/files/vevex.pdfIn PDF document text
    • http://scoutpate.com/userfiles/file/69225027077.pdfIn PDF document text
    • http://champagne-marc-chauvet.com/images/files/mupenalurenufegezogosuse.pdfIn PDF document text
    • https://davebakeragency.com/wp-content/plugins/super-forms/uploads/php/files/9ba1e4b51ef5dae48cea30e6a753b684/34994943684.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a6edf99158b---85881658888.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607b952ccc154---95064678429.pdfIn PDF document text
    • http://princeworldwide.com/multimedia/userfiles/file/boxunetilobitigamugisar.pdfIn PDF document text
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/daaaec1544a29e2ca05eca885376d3ae/49033341578.pdfIn PDF document text
    • https://www.popcaffe.it/wp-content/plugins/super-forms/uploads/php/files/7bffffdfecb3f9a6359fb2ddad69a945/61170558978.pdfIn PDF document text
    • http://creativeindustries.ru/uploads/userfiles/file/49408574226.pdfIn PDF document text
    • https://canadianrelocation.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606d4c4d5032b---varos.pdfIn PDF document text
    • https://dongcohonda.com/userfiles/file/monejasov.pdfIn PDF document text
    • http://ippinnudon.com/uploads/files/40327385087.pdfIn PDF document text
    • https://adlinefor.com/home/webagen/public_html/korn/data/file/99212170854.pdfIn PDF document text
    • http://caratow.nl/userfiles/file/vosojilubipuwiwelowa.pdfIn PDF document text
    • https://equator-maritime.com/userfiles/file/lupizilipolupalekoke.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/34aebc2b08eab9d9da7bdf15deee5afb/80590816129.pdfIn PDF document text
    • http://kapelski.pl/userfiles/file/beroneripukamoga.pdfIn PDF document text
    • https://diversified-nj.com/wp-content/plugins/super-forms/uploads/php/files/17126baee67255a56c3d3fb9cfccfda3/6219889233.pdfIn PDF document text
    • https://endoaccessories.com/wp-content/plugins/super-forms/uploads/php/files/78j1nivo8lm9hnfccqbmi5je0e/18174886253.pdfIn PDF document text
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/cem41q6kbpts30ia23ccak1qjs/mebiju.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/fkk8v58tkik867n4hl6epk23k6/11182816238.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=square+root+by+factorisation+methodPDF 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_off0000cec1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEC1 11272 bytes
SHA-256: bf2c2b61e72c2159c7d12c8b434bf670705b04483b8a782655592739e422f769
font_01_sfnt_off0000e8d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8D6 16840 bytes
SHA-256: 7967f98f33a9bcd24a4eabd1962de9f43f87a11f63752b344022b1c8f1467571
font_02_sfnt_off00011520.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11520 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1