Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5c553cdc6cd36a5…

MALICIOUS

PDF

121.4 KB Created: 2021-08-19 11:22:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 785de5a2f8b6d7c2f769cb828b957517 SHA-1: cba9eb6c42f5d763788342631ff6df0c0de3af21 SHA-256: f5c553cdc6cd36a5b84beec9151a31b9805edc39ddb858b251a1b1a2975b5ff4
156 Risk Score

Malware Insights

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

The sample was detected by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier flagged it with high confidence. It contains numerous URLs, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users. The ML_NYX_PDF_MALICIOUS heuristic and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://arrayamed.com/userfiles/file/67487397035.pdf In PDF document text
    • http://whatdwellswithin.com/file/86208494582.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1606c8059d1f82---damakotul.pdfIn PDF document text
    • https://bangprice.combangprice.com/beta/cms_image/file/71849503483.pdfIn PDF document text
    • https://abandassociates.com/ckfinder/userfiles/files/fubefimozezevujugabojuwe.pdfIn PDF document text
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609464863c44b---57263272178.pdfIn PDF document text
    • http://udmvdpo.ru/images/files/tivuwirowozizidopuf.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/86795289562.pdfIn PDF document text
    • https://cakenepal.com/userfiles/file/telosotofusibojesite.pdfIn PDF document text
    • http://3xlove.com/uploadfile/file/tisolalitubizapulunagu.pdfIn PDF document text
    • http://gezond-trakteren.nl/kasteel-doornenburg-img/bestandenfile/pujabekaxigamufozidux.pdfIn PDF document text
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/e91a7db362d8d38a994709c08e2cf834/22894330090.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/kedepepofiluxofibafud.pdfIn PDF document text
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e63c3808e95---likuwefebaleseriziluxak.pdfIn PDF document text
    • https://vrrc.heart.net.tw/ckfinder/ckfiles/files/72251069795.pdfIn PDF document text
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9dde869a7---pemodovuwimapamipu.pdfIn PDF document text
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/efabedfa897dbe638ec0ffc5922a7dff/napokataniwekonuxawaz.pdfIn PDF document text
    • https://angkaganjil.com/contents/files/53552323167.pdfIn PDF document text
    • https://bahamianbrewery.com/ckfinder/userfiles/files/8026696241.pdfIn PDF document text
    • https://netcsemege.hu/ckfinder/userfiles/files/pogevo.pdfIn PDF document text
    • http://agriturismolescuderie.eu/userfiles/files/93160690421.pdfIn PDF document text
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/rsqiqu0pnsjt5tg78sp4ijcch4/badoka.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b42d23633b9---kedup.pdfIn PDF document text
    • http://tanriovermensucat.com/uploads/genel/files/migubopud.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=beretta+a350+xtrema+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_off000162cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x162CB 27228 bytes
SHA-256: 32d3b62e1e458bb5ebb647c7f15429849698262d38befb2da3d093a624f13e2f
font_01_sfnt_off0001a791.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A791 10572 bytes
SHA-256: 2ac695ccf737a1a4a2abddac76151111fc321f5b6b267cfb28f9b11a15d20551
font_02_sfnt_off0001bfc2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1BFC2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1