Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb5fcd0e66c8e4f9…

MALICIOUS

PDF

88.3 KB Created: 2021-08-18 22:36:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 7a53fa3ebe718012479d70fc9a7f8816 SHA-1: c8405f52bbdbbcbbb82f8f5a5b694b817fe7ef42 SHA-256: cb5fcd0e66c8e4f9548686b1a11ca611f452e06228fd5b3a82cba270af6679ce
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the document functions as a link farm, with numerous URLs pointing to compromised CMS uploads and disposable hosting, likely intended to lure users into clicking malicious links. No scripts were extracted from this sample, and the document body was unreadable.

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 http://yfatc.com/userfiles/file/tomoxil.pdf In PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a547e60adbb---mafozexavisijumudaz.pdfIn PDF document text
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/1749751e302b7daae95c789b65e707d4/narabobimunifikikowej.pdfIn PDF document text
    • http://infrabud.eu/fckpliki/file/7387861574.pdfIn PDF document text
    • http://partnerplus30.ru/images/fornews/files/83205789969.pdfIn PDF document text
    • https://canadianrelocation.net/wp-content/plugins/formcraft/file-upload/server/content/files/160d86d1f23995---14069690569.pdfIn PDF document text
    • https://bawwabatrizq.com/userfiles/file/41281548671.pdfIn PDF document text
    • https://aadhaarretail.com/administrator/imagetemp/file/70210093327.pdfIn PDF document text
    • https://phoenixknights.co.uk/wp-content/plugins/super-forms/uploads/php/files/f2f6deecdfd9e09f33d225789ae13ed8/51467475296.pdfIn PDF document text
    • http://moodyhighclassof70reunion.com/clients/2/24/24f6aee67edc386a60746049a176a33b/File/xijibij.pdfIn PDF document text
    • http://loadcell.vn/Images_upload/files/40589909160.pdfIn PDF document text
    • http://alotercuman.com/ckfinder/userfiles/files/93997938296.pdfIn PDF document text
    • http://seventyfirstclassof69.com/clients/60772/File/39452129253.pdfIn PDF document text
    • http://toyotaquangninh.org/data/dulieu/files/rofelazeku.pdfIn PDF document text
    • http://luxmeterthai.com/ckfinder/userfiles/files/22500915768.pdfIn PDF document text
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/4b864dac4ad3298b0cb479a7845fd6c2/kepisaxupewifanoji.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/0f8fd5ed821c8fc8b510f33ed31c7753/nizibefalisebakufirebaniz.pdfIn PDF document text
    • http://obasekiestates.com/UserFiles/file/18781075915.pdfIn PDF document text
    • http://kowalstwwo.pl/public/cms//images/file/32892608904.pdfIn PDF document text
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607403ca5478d---66821121849.pdfIn PDF document text
    • https://justbuymeds.net/userfiles/file/15300158452.pdfIn PDF document text
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ed7d117874---6243701881.pdfIn PDF document text
    • https://baohohoanglong.com/userfiles/file/kubovavamifu.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160e29a5cdf5f7---2318256288.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=what+is+scope+and+delimitation+samplePDF 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_off0000f268.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF268 18964 bytes
SHA-256: d96669c2ea93624212e2a177358fa0b0c290f3d15347341f1a2e5a48ab51ee12
font_01_sfnt_off0001230b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1230B 10672 bytes
SHA-256: 1038ef2b99696109e0b842bba500a45f6ddd96906947c69397078ffac58adcb4
font_02_sfnt_off00013b58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B58 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1