Malicious PDF — malware analysis report

Static analysis result for SHA-256 451c4a5e342e191f…

MALICIOUS

PDF

88.6 KB Created: 2021-06-28 12:01:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 39a9c959f18afe868886e42ac1043715 SHA-1: e6f860a00e8902fe2a01fa4a7ef236a1524ae1c2 SHA-256: 451c4a5e342e191f97b99ec3d9990ac5328d0d046a7250bcfd3d00b7dcfab565
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple links pointing to compromised WordPress sites, identified by heuristics like 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM'. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery. Although no scripts were explicitly extracted, the nature of the links suggests the PDF is designed to redirect users to malicious content, aligning with spearphishing tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9822

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/1ut02nbgm2dus2e5qklsjqq4hj/tuvozixanodasoxawuvab.pdf In PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/46724538685.pdfIn PDF document text
    • http://doublehappyvstheinfinitesadness.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a236f7173a---xufadamekazapu.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/1607b93f5cb208---zexojuwusifipi.pdfIn PDF document text
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/160928e89185f2---99183943624.pdfIn PDF document text
    • https://www.businesswatchguardingservices.co.uk/wp-content/plugins/super-forms/uploads/php/files/1e5seg7nkg6lruige566q90uhf/kinitawidifalawunitu.pdfIn PDF document text
    • https://abugfreemind.com/userfiles/file/48257362411.pdfIn PDF document text
    • http://sklepjola.pl/userfiles/file/19420978155.pdfIn PDF document text
    • http://www.bordadoindustrial.com/ckfinder/userfiles/files/31419224747.pdfIn PDF document text
    • http://mosjob.ru/images/file/gojegabomofumufutozeli.pdfIn PDF document text
    • https://www.mnspineandsport.com/wp-content/plugins/super-forms/uploads/php/files/00d422f44fabcbba686c74286adcef5d/tepawexufukajika.pdfIn PDF document text
    • https://www.kunapak.com/wp-content/plugins/super-forms/uploads/php/files/frm83kt4573tfb34ic9v7jg8j4/6572360094.pdfIn PDF document text
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/hbhij4mubtgs5dlhn065881iib/32578569652.pdfIn PDF document text
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/16076ebe5a08d4---gitixeso.pdfIn PDF document text
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/d2c4a61d02dd39996d132db0f7d4a63b/37393053938.pdfIn PDF document text
    • http://tafoto.de/img/upload/files/sotolojotawuxawapovobotaz.pdfIn PDF document text
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/160935406c9188---begabexedi.pdfIn PDF document text
    • http://modnyi-buket.ru/uploads/files/82559738594.pdfIn PDF document text
    • https://xn----7sbbjg7ctfs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/38dcb91e2ce48a1c9eeae07534beb3d2/1224081146.pdfIn PDF document text
    • http://stark-tools.ru/images/uploaded/5803296804.pdfIn PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160af8053ab802---98361273802.pdfIn PDF document text
    • http://4seasonstours.in/userfiles/file/gidigotatigolok.pdfIn PDF document text
    • https://mides.vn/images/ckeditor/files/mituj.pdfIn PDF document text
    • http://landpas.pl/upload/file/woxet.pdfIn PDF document text
    • http://mebco.ru/images/file/14179429681.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a39ddd7ad7c---62190818097.pdfIn PDF document text
    • http://emannsltd.com/userfiles/8586166102.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=partial+differential+equations+with+fourier+series+and+boundary+value+problems+solutionsPDF 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_off0000f362.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF362 11416 bytes
SHA-256: ae9118c4b1add3f6ab29107c46cbff0bc56a4b657fca9d1398c38ab013153177
font_01_sfnt_off00010dba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DBA 17656 bytes
SHA-256: 7442ef2451395c97871b1ad83e17c264a8be878e06c4e351ca19505f67cedac6
font_02_sfnt_off00013baa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13BAA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1