Malicious PDF — malware analysis report

Static analysis result for SHA-256 41d356a6341e8b08…

MALICIOUS

PDF

84.2 KB Created: 2021-09-07 13:17:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 296bc505552f8e398cd9784b26808c5a SHA-1: e98a70201a5dc71cf1a31f9a5f0bfb0deec6b0ae SHA-256: 41d356a6341e8b08e732b893f032f1bc1006a334dd0045a2cb86dc2198057e84
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. Heuristics identified it as a link farm pointing to numerous external URLs, many hosted on potentially compromised or disposable domains. The PDF structure itself appears to be a lure, directing users to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://jxloanchien.com/style/postimage/file/56254118098.pdf In PDF document text
    • https://southafricapools.com/contents//files/99968350966.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608721e5ba59d---jadumikitapogu.pdfIn PDF document text
    • http://lamorenj.com/userfiles/files/21036415739.pdfIn PDF document text
    • https://www.wemservice.com/ckfinder/userfiles/files/45359361732.pdfIn PDF document text
    • https://ijfbacknumber.com/editor_up/98291666182.pdfIn PDF document text
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161338a1419484---6725520330.pdfIn PDF document text
    • https://suprizpin.com/calisma2/files/uploads/satufopuxevudot.pdfIn PDF document text
    • https://www.kalirich.com/wp-content/plugins/super-forms/uploads/php/files/7of0aujnfn9huvs9c5iam6qjm2/42125872748.pdfIn PDF document text
    • https://clickkedai.com/userfiles/file/83178409085.pdfIn PDF document text
    • https://kudamatsu.org/userfiles/file/77716978276.pdfIn PDF document text
    • http://bsp-plovdiv.org/ckfinder/userfiles/files/19719886000.pdfIn PDF document text
    • https://ncvpte.in/userfiles/file/musijexu.pdfIn PDF document text
    • http://svx.su/ffile/file/degazelekibesizot.pdfIn PDF document text
    • http://faxik.ru/ckfinder/userfiles/files/xovinekezis.pdfIn PDF document text
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/614d2a92c06183e082d03f94bffd55cd/gukotujowujuj.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d2f99a20aee---dikizefixara.pdfIn PDF document text
    • http://ediliziaunoaventi.com/userfiles/files/narasu.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5ec958e291---23257542929.pdfIn PDF document text
    • https://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/f330cae9a08f987539cbd3c85ed0fbcf/vibutugen.pdfIn PDF document text
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160e4e0aa4bbe2---vaduvedefuxide.pdfIn PDF document text
    • https://interesttour.com/wp-content/plugins/super-forms/uploads/php/files/501cdf424a4ab7f23ef89e4c07f7372b/vezamukotifizodadupule.pdfIn PDF document text
    • http://studiotipaldo.com/userfiles/files/jafigovoliw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=pdfkit+ios+githubPDF 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_off0000e7de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7DE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fff5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFF5 10424 bytes
SHA-256: 9438e0ad39375180be3bce52708154ed50b37a2cd91e5bd717e863aaa58902bf
font_02_sfnt_off0001177b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1177B 16968 bytes
SHA-256: d5971ade50d093099f159b7ad3f6b112119c2587519d706d474a0b3cea80c572