Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4ae5ababbfaa69e…

MALICIOUS

PDF

122.4 KB Created: 2021-07-07 03:51:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 43ea179782042052470653a27240d4e3 SHA-1: 51efd7e66cf32f8579d9363cd6dea6b7e5634844 SHA-256: c4ae5ababbfaa69e7db7b543b1d96e41d0654395cd093326a51b11bf01cda5c3
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to other PDF files hosted on compromised CMS upload directories. These links likely serve to obscure the true malicious destination or to distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9795

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://omomediacion.com/wp-content/plugins/super-forms/uploads/php/files/62ec898988a8ba4c5d98aaf362a53823/vamujopukelibawifofuginig.pdf
    • http://ampletrekking.com/userfiles/file/zibijazike.pdf
    • https://elsa-daulte.com/ckfinder/userfiles/files/91079711440.pdf
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b772f154584---godogagamen.pdf
    • http://altelaw.com/uploads/image/file/74317969227.pdf
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca0e44b729---lijivinaladexobewerufivi.pdf
    • https://kopari.hu/files/file/gubaj.pdf
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d257746b6f0---36404486465.pdf
    • http://penzionklara.cz/userfiles/file/tosoraxufanijevon.pdf
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aeb9595cef7---50751135940.pdf
    • https://churchosonline.com/wp-content/plugins/super-forms/uploads/php/files/0e97e48bb6fc979f6388d4fe36fbb5c8/34750368522.pdf
    • https://www.rowtheerne.com/wp-content/plugins/super-forms/uploads/php/files/0354db3af0827b61e7c7fd1cac640af7/51253929883.pdf
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/160c1cf2dc384c---16426436666.pdf
    • http://aliceinformaticasrl.com/user/pages/tazevaka.pdf
    • http://livestreaming.group/wp-content/plugins/super-forms/uploads/php/files/bma5atpm3tf49hmpqa6rlao0lvk3t0b3/44620778630.pdf
    • https://mimpiindah88.com/contents//files/xufegopijevakesuzuxe.pdf
    • http://jnnycc.org/userfiles/file/60970148802.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160df06b070482---71960656455.pdf
    • http://nfc-lampang.com/user_img/files/97869813074.pdf
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/160741e18ea1b9---zukidomudotukafi.pdf
    • http://nbnjl.com/userfiles/files/buvubati.pdf
    • http://imaginove.eu/data/Files/40492064113.pdf
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160771d1f6d746---39303496018.pdf
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160969f010936f---21096229113.pdf
    • https://careeraccelerators.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160793d14ca96f---juvogoxogane.pdf
    • http://roocenter.ru/upload/file/70776932141.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=tourist+trade+meaning
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off00018cd0.bin
7f49cc5153c56447dc1faae9805e7e05e374625d935a6c251060878d3be194bc
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x18CD0 18868 bytes
font_00_sfnt_off00015a4f.bin
68d449b0a658ed527ca5c096ac4dc38edecb0c77af199462222ef789c678c209
pdf-font-stream PDF embedded font (sfnt) at offset 0x15A4F 19888 bytes
font_02_sfnt_off0001ab85.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1AB85 16792 bytes
font_03_sfnt_off0001c39c.bin
f3e32f57d2e63c43ed158f1b2ec76f8cbb52defb1b62be8fdc99d2e3c765a9bb
pdf-font-stream PDF embedded font (sfnt) at offset 0x1C39C 10608 bytes