Malicious PDF — malware analysis report

Static analysis result for SHA-256 ced57b2454a7a61e…

MALICIOUS

PDF

76.5 KB Created: 2021-07-31 22:26:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0967c48ec24288f41e1800f248d380a8 SHA-1: 554eadc6e57b89ef7d46216a37927d796a2640e9 SHA-256: ced57b2454a7a61ed3e99561e6830cc655c174050b398b962e714251f8f51b97
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs that point to other PDF files hosted on various domains, some of which appear to be compromised WordPress installations. The presence of these links suggests a phishing or malware distribution scheme, where users are lured to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://synerhu.ru/uplcv?utm_term=carl+flesch+scale+system+double+bass
    • https://satybharat.com/ci/userfiles/files/50094631033.pdf
    • https://dcimx.com/files/kimofani.pdf
    • http://buchtel1967.com/clients/26382/File/33294237441.pdf
    • http://centrons.com/uploaded/file/79552003960d4dac436441.pdf
    • http://ajivikafinance.com/userfiles/file/24930092192.pdf
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/16075814645102---19798237687.pdf
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160d61aecd0ab9---26024096138.pdf
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160831bd39dfc8---41462191131.pdf
    • https://mariellatriolo.it/public/file/gogiritatovupe.pdf
    • https://pmms-online.com/assets/file/nuremokapapotazoxavadag.pdf
    • http://bright-inter.com/file_media/file_image/file/33124871286.pdf
    • http://timelessmebel.ru/wp-content/plugins/super-forms/uploads/php/files/81a532a3cf3615c443ee9938c3e4b03c/zevik.pdf
    • https://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/d6a9c47de02a6818afce7922d586f97a/rufoxikulewusixajuped.pdf
    • https://irastuff.com/admin/ckfinder/uploads/files/xegowovabazajem.pdf
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607df79f3f9e9---vinaxegevuze.pdf
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096d7c6780e9---xudorutitopegufebupekosuv.pdf
    • https://m-isc.com/userfiles/file/japunireligupoxu.pdf
    • http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/a16335135744b8574630908b20816552/likefegek.pdf
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160b0632f9d3e0---44240490641.pdf
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f3b009cb1a---94836068522.pdf
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3c4a256327---susidek.pdf
    • http://lawcab.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a1ae29d0257---xonejujibefoturolox.pdf
    • https://www.sehersirin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c1c5174509---xaziwefubagaselowulules.pdf
    • http://tavernadelsnoguers.com/wp-content/plugins/super-forms/uploads/php/files/1ac0f6d79a652788e6e835d429ec2e28/59753289405.pdf
    • http://thuaphatlailongthanh.com/upload/contentFile/minhchau/file/32442464805.pdf
    • http://dent-pro.cz/pic/file/miwowipenezod.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c5ed.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC5ED 16792 bytes
font_01_sfnt_off0000ddff.bin
85e48b3528e8fa46b8209e4d4b4122014be116afefdb63b363f31aac6d482704
pdf-font-stream PDF embedded font (sfnt) at offset 0xDDFF 16540 bytes
font_02_sfnt_off00010950.bin
5ef011b6d5efc15cbf1ed7313bf9f0d704949557f054a987344ec463e8e4c102
pdf-font-stream PDF embedded font (sfnt) at offset 0x10950 10932 bytes